Updated for Backbone 1.1, Marionette 1.8.x. Update to use wreqr, bindTo -> listenTo

Application.root.js

define([
    "underscore",
    "backbone",
    "marionette",
    "vent"
],

/**
 * Creates the primary `Marionette.Application` object that runs the admin framework.  Provides a central point
 * from which all other sub-applications are started, shown, hidden, and stopped.
 * @requires module:underscore
 * @requires module:backbone
 * @requires module:marionette
 * @requires module:supervent // this is a custom eventAggregator with Wreqr.commands() and Wreqr.reqres() properties
 */
function (_, Backbone, Marionette, vent) {

    var rootApp = new Marionette.Application(),
        subApps = {};

    rootApp.subApps = subApps;

    rootApp.addRegions({
        body: "body"
    });

    rootApp.addInitializer(function (options) {
        var i, il, anApp;
        var that = this;

        rootApp.router = new options.Router({
            controller: options.controller
        });

        // All routers in the `applications` array should be Marionette.SubAppRouters.  When the router is instantiated,
        // the first parameter passed to the constructor (`anApp.name`) is interpreted as the prefix for all `routes`
        // and `appRoutes` in the router.  All routes will have the prefix prepended to them, then a forward slash, then
        // the "regular" route.  For example, if you have a route that's `search/:id` and the prefix is "library", then
        // the actual route added to Backbone will be `library/search/:id`.
        for(i= 0, il=options.applications.length; i<il; i++) {
            anApp = options.applications[i];

            // TODO: should we hook this up here, or send out an event that tells apps where to display themselves?
            anApp.parentRegion = that.body;
            anApp.application.router =
                new anApp.Router(anApp.name, {
                    controller: anApp.controller
                });

            subApps[anApp.name] = anApp.application;
        }
    });

    rootApp.on("initialize:after", function () {
        var that = this;
        // Start all of our sub-applications
        _.each(subApps, function(app, key, list){
            // notice we pass this app's region to the sub-app, so it can either grab the $el or use the region directly
            app.start({parentRegion: that.body});
            // Trigger a notification and pass the app along in case anyone wants a reference
            vent.trigger("starting:app:" + key, app);
        });

        // And hook up history tracking
        if (Backbone.history) {
            Backbone.history.start();
        }
    });

    // Now actually display the application
    rootApp.on("start", function () {
        vent.trigger("started:app:rootapp", rootApp);
        vent.commands.execute("initialize:ui");
    });

    return rootApp;

});

main.js

//main.js
require([
    'app',
    'router',
    'controller',
    'subapp/app',
    'subapp/router',
    'subapp/controller'
],

function(rootApp, AppRouter, AppController, subApp, SubAppRouter, SubAppController){

    "use strict";

    var options = {
            controller: AppController,
            Router: AppRouter,
            applications: [
                 {
                    name: "contestcreator",
                    application: subApp,
                    controller: SubAppController,
                    Router: SubAppRouter
                }
            ]
        };

    rootApp.start(options);

});

Marionette.SubAppRouter.js

// This is heavily based on Backbone.SubRoute (https://github.com/ModelN/backbone.subroute) by Dave Cadwallader, who
// helped me out in this discussion thread:
// https://groups.google.com/forum/?fromgroups=#!topic/backbone-marionette/KTw7USoA6Gs
define([
    'underscore',
    'marionette'
],

/**
 * A module that defines and adds Marionette.SubAppRouter to the Marionette object
 * @module marionette.subapprouter
 * @requires module:marionette
 * @param {Function} Marionette - Marionette.js
 * @exports marionette
 */
function(_, Marionette) {

    /**
     * Creates an AppRouter with a particular prefix at the beginning of each route.
     * @class Marionette.SubAppRouter
     * @alias module:marionette.subapprouter
     * @classdesc A router that prepends a specified prefix (passed on instantiation) onto each specified `route` or
     * `appRoute`.  Directly extends from Marionette.AppRouter to enable controller objects linked to the `appRoutes`
     * hash. Useful for sub applications that live in sub-directories under root and want to handle all of their own
     * routing.
     */
    Marionette.SubAppRouter = Marionette.AppRouter.extend({

        /**
         * @constructs Marionette.SubAppRouter
         * @param {string} [prefix] - The prefix string to prepend to all routes, making them act as if relative. If
         * blank, then it just acts like a regular Backbone.Router.
         * @param {Object} [options] - The options object expected by Marionette.AppRouter.
         * @param {Object} [options.controller] - An object with function properties corresponding to the hash values
         * from `routes` and `appRoutes`.
         */
        constructor: function(prefix, options) {

            var controller,
                appRoutes,
                routes = {};

            // Prefix is optional, set to empty string if not passed
            this.prefix = prefix = prefix || "";

            // SubRoute instances may be instantiated using a prefix with or without a trailing slash.
            // If the prefix does *not* have a trailing slash, we need to insert a slash as a separator
            // between the prefix and the sub-route path for each route that we register with Backbone.
            this.separator =
                    ( prefix.slice( -1 ) === "/" )
                            ? ""
                            : "/";

            // if you want to match "books" and "books/" without creating separate routes, set this
            // option to "true" and the sub-router will automatically create those routes for you.
            var createTrailingSlashRoutes = options && options.createTrailingSlashRoutes;

            if(this.appRoutes) {

                appRoutes = this.appRoutes;
                controller = this.controller;

                if(options && options.controller) {
                    controller = options.controller;
                }

                _.each(appRoutes, function(callback, path) {

                    if (path) {

                        // strip off any leading slashes in the sub-route path,
                        // since we already handle inserting them when needed.
                        if (path.substr(0) === "/") {
                            path = path.substr(1, path.length);
                        }

                        routes[prefix + this.separator + path] = callback;

                        if (createTrailingSlashRoutes) {
                            routes[prefix + this.separator + path + "/"] = callback;
                        }

                    } else {
                        // default routes (those with a path equal to the empty string)
                        // are simply registered using the prefix as the route path.
                        routes[prefix] = callback;

                        if (createTrailingSlashRoutes) {
                            routes[prefix + "/"] = callback;
                        }
                    }

                }, this);

                // Override the local sub-routes with the fully-qualified routes that we just set up.
                this.appRoutes = routes;

            }

            Marionette.AppRouter.prototype.constructor.call(this, options);
        }

    });

    return Marionette.SubAppRouter;

});

vent.echovent.js

// This is heavily over-engineered, honestly, as you should really only need a single vent across which
// to echo (which should be the "root" vent in your project).  But since I bothered to make it more flexible,
// I figured I'd put up the more flexible version rather than the single-echo version I'm currently using.
// underscore.deepclone is just a module that adds the "cloneDeep" method from lo-dash to underscore, which
// is documented here: http://lodash.com/docs#cloneDeep
define([
    'underscore',
    'marionette',
    'wreqr',
    'vent',
    'vent.super',
    'underscore.deepclone'
],

    /**
     * @module components/Vent.echo-supervent
     * @requires module:underscore
     * @requires module:Marionette
     * @requires module:Wreqr
     * @requires module:vent
     * @requires module:base/Vent.super
     */
    function(_, Marionette, Wreqr, rootVent, SuperVent){

        var console = window.console;
        var getOpt = Marionette.getOption;

        var nullOrEmpty = function(obj) {
            return (!obj || (obj && _.isEmpty(obj)));
        };

        var isVent = function(obj) {
            return (obj instanceof Wreqr.EventAggregator);
        };

        /**
         * @alias module:components/Vent.echo-supervent
         * @constructor
         * @param {String} namespace - The namespace to prepend onto events when echoing
         * @param {Object} options - A hash of
         */
        var EchoVent = SuperVent.extend({

            /**
             * The namespace to prepend onto events when echoing back across the root vent
             * @property namespace
             * @type String
             * @default ""
             */
            namespace: "",

            echoOn: {},

            debug: false,

            constructor: function(namespace, vents, options) {

                var args = _.toArray(arguments);
                var that = this,
                    config = args[0];

                // Handle the one-big-config-param case
                if (args.length === 1 && _.isObject(config) && !isVent(config)) {
                    namespace = config.namespace || this.namespace;
                    vents = config.echoOn || this.echoOn;
                    options = _.omit(config, ["namespace", "vents"]);
                }

                this.options = options || {};

                this.debug = getOpt(this, "debug");

                // Call the superclass constructor to get event binder mixed in early
                SuperVent.prototype.constructor.apply(this, arguments);

                this.namespace = namespace;

                if (!nullOrEmpty(vents)) {
                    this._addInitialVents(vents);
                }

                // We want any event send through this aggregator to echo in the root vent as well - just prefixed by
                // a namespace (the name of the app/module, typically)
                this.bindTo(this, "all", function(){
                    var args = _.toArray(arguments);
                    var originalName = args[0];
                    var vents = that.echoOn;

                    // prefix namespace to event name
                    args[0] = [that.namespace, originalName].join(":");

                    // re-trigger that event on every registered vent
                    _.each(vents, function (vent) {
                        vent.trigger.apply(vent, args);
                        if (that.debug) {
                            console.log("event \"%s\" triggered on %o with args %o", args[0], vent, _.rest(args, 1));
                        }
                    });
                });
            },

            _addInitialVents: function(vents) {

                var echoOn = nullOrEmpty(vents) ? false : vents,
                    that = this;

                // Return if there's nothing to do
                if (!echoOn) { return; }

                // Clear current list of vents (we still have existing ones in the temp clone)
                this.echoOn = {};

                var addEach = function(vent, key) {
                    var args = _.toArray(arguments);
                    // We don't want pure numeric indexes as custom IDs, so if we've gotten this via an array, set
                    // it to null so addEcho will generate a valid unique ID.
                    if (_.isNumber(key)) { args[1] = false; }
                    that.addEcho.apply(that, args);
                };

                // If it's an array, or it's an object with id/aggregator pairs, go ahead and run it through addEach
                if (isVent(echoOn)) {
                    this.addEcho(echoOn);
                } else if (_.isArray(echoOn) || _.isObject(echoOn)) {
                    _.each(echoOn, addEach);
                } else {
                    var msg = "Cannot add object to EchoVent with namespace " + this.namespace + ", unknown object";
                    var err = new Error(msg);
                    err.catalyst = echoOn;
                    throw err;
                }
            },

            setNamespace: function(newNs) {
                this.trigger("echovent:change:namespace:from:" + this.namespace + ":to:" + newNs, this);
                this.namespace = newNs;
            },

            addEcho: function(newVent, customIndex) {
                customIndex = customIndex || _.unique("ev_");
                this.echoOn[customIndex] = newVent;
                this.trigger("echovent:added:vent", newVent);
            },

            removeEcho: function(vent) {
                var vents = this.echoOn;
                var ventName = _.isString(vent) ? vent : this.getIdOf(vent);
                vent = vents[ventName];
                this.trigger("echovent:removed:vent:" + ventName, vents[vent]);
                delete vents[ventName];
            },

            getIdOf: function(vent) {
                var vents = this.echoOn;
                if (nullOrEmpty(vents)) { return false; }
                var vals = _.values(vents);
                var index = vals.indexOf(vent);
                return _.keys(vents)[index];
            }

        });

        return EchoVent;

    });

vent.super.js

define([
    'backbone',
    'marionette',
    'wreqr'
],
/**
 * A module that exports `SuperVent` - simply an event aggregator that has all the different `Wreqr` functionality
 * built in.  Should only be used by the root application, all other applications should use `EchoVent`.
 * @module supervent
 * @requires module:backbone
 * @requires module:Marionette
 * @requires module.Wreqr
 * @exports SuperVent
 */
function(Backbone, Marionette, Wreqr) {

    var SuperVent = {};
    
    Wreqr.EventAggregator.extend = Backbone.Model.extend;

    /**
     * An event aggregator with Wreqr.Commands and Wreqr.RequestResponse objects added.
     * @class SuperVent
     * @alias module:supervent
     * @classdesc A `Marionette.EventAggregator` object with `Wreqr.Commands` and `Wreqr.RequestResponse` instances
     * built in.
     * @property {Backbone.Wreqr.Commands} commands - A Wreqr.Commands instance
     * @property {Backbone.Wreqr.RequestResponse} reqres - A Wreqr.RequestResponse instance
     */
    SuperVent = Wreqr.EventAggregator.extend({

        /**
         * @constructs SuperVent
         */
        constructor: function(debug){

            this.debug = debug || false;

            // And here's why it's a Super Vent
            this.commands = new Backbone.Wreqr.Commands();
            this.reqres = new Backbone.Wreqr.RequestResponse();

            // Call the superclass constructor to get event binder mixed in
            Wreqr.EventAggregator.prototype.constructor.apply(this, arguments);
            if (this.debug) {
                this.listenTo(this, "all", this.logToConsole, this);
            }
        },

        logToConsole: function() {
            var args = Array.prototype.slice.call(arguments);
            var eventName = args[0];
            console.log("vent triggered :%s with args %o", eventName, args.slice(1));
        }

    });

    return SuperVent;

});