Used @ http://cacodaemon.de/index.php?id=30

ChatServer.js

"use strict";
var User = require('./User.js').User;
var Message = require('./Message.js').Message;
var PrivateMessage = require('./Message.js').PrivateMessage;
var Command = require('./Message.js').Command;
var SessionHandler = require('./SessionHandler.js').SessionHandler;

module.exports.ChatServer = function (port, debug) {
	var http = require('http');
	var qs = require('querystring');
	var url = require("url");

	var sessionHandler = new SessionHandler();

	var clientCounter = 0;
	var port = port ? port : 8888;
	var debug = debug ? debug : false;

	this.forEachUser = function (callBack) {
		sessionHandler.forEachSession(function(session) {
			if (!session.user) {
				return;
			}

			callBack(session.user);
		});
	}

	this.getUsers = function () {
		var users = new Array();
		sessionHandler.forEachSession(function(session) {
			if (!session.user || !session.user.loggedin) {
				return;
			}

			users.push(session.user);
		});

		return users;
	}

	this.getUserByName = function (name) {
		var searchUser = null;
		this.forEachUser(function (user) {
			if (user.name == name) {
				searchUser = user;
			}
		});
		return searchUser;
	}

	this.removeUser = function (user) {
		sessionHandler.deleteSession(user.session);
		this.addMessageToAll(new Command('removed_users', new Array(user)));
	}

	this.addMessageToAll = function (msg) {
		this.forEachUser(function (user, i) {
			user.addMessage(msg);
		});
	}

	this.command = function (user, command) {
		switch (command.name) {
			case 'change_name':
				this.addMessageToAll(new Command('name_changed', {from: user.name, to: command.params.newName, user: user}));
				user.name = command.params.newName;
				break;
			case 'login':
				user.name = command.params.name;
				user.loggedin = true;
				this.addMessageToAll(new Command('new_user', {user: user}));
				user.addMessage(new Command('welcome', command.params));
				break;
			case 'logout':
				this.removeUser(user);
				break;
			case 'users':
				this.addMessageToAll(new Command('users', this.getUsers()));
				break;

		}
	}

	this.perform = function (session, msg) {
		var user = session.user;

		switch (msg.type) {
			case 'normal':
				this.addMessageToAll(new Message(msg.text, msg.type, user));
				break;
			case 'private':
				var recipient = this.getUserByName(msg.recipient);
				var privateMessage = new PrivateMessage(msg.text, user, recipient);
				recipient.addMessage(privateMessage);
				user.addMessage(privateMessage);
				break;
			case 'command':
				this.command(user, msg);
				break;
		}
	}

	var thath = this;
	http.createServer(function (request, response) {
	    var query = url.parse(request.url, true).query;
	    var session = sessionHandler.getSession(request, response);

	    if (!session.user) {
	        session.user = new User('User_' + ++clientCounter, session);
	    }

	    if (query.q) {
	        var clientMessage = JSON.parse(decodeURIComponent(query.q));
	        thath.perform(session, clientMessage);
	    }

	    response.writeHead(200, {'Content-Type': 'application/x-javascript'});
	    if (query.ChatResponse) {
	        response.end(query.ChatResponse + '(' + JSON.stringify(session.user.messages()) + ');');
	    }
	    else {
	        response.end(JSON.stringify(session.user.messages()));
	    }
	}).listen(port);
}

Message.js

module.exports.Message = function (text, type, user) {
	var text = text;
	var type = ['normal', 'private', 'command'].indexOf(type) !== -1 ? type : 'normal';
	var user = user;
	var time = new Date().getTime();

	this.toString = function (msg) {
		return text;
	}

	this.toJSON = function() {
		return {
			text: text,
			type: type,
			user: user,
			time: time
		};
	}
}

module.exports.PrivateMessage = function (text, user, recipient) {
	var text = text;
	var type = 'private';
	var recipient = recipient;
	var time = new Date().getTime();

	this.toString = function (msg) {
		return text;
	}

	this.toJSON = function() {
		return {
			text: text,
			type: type,
			user: user,
			recipient: recipient,
			time: time
		};
	}
}
module.exports.PrivateMessage.prototype = new module.exports.Message ();

module.exports.Command = function (name, params) {
	if (!params instanceof Array) {
		params = new Array(params);
	}

	var name = name;
	var params = params;
	var type = 'command';
	var time = new Date().getTime();

	this.toString = function (msg) {
		return name;
	}

	this.toJSON = function() {
		return {
			name: name,
			params: params,
			type: type,
			time: time
		};
	}
}
module.exports.Command.prototype = new module.exports.Message ();

User.js

var Message = require('./Message.js').Message;
var PrivateMessage = require('./Message.js').PrivateMessage;
var Command = require('./Message.js').Command;

module.exports.User = function (name, session) {
	this.name = name;
	this.session = session;
	var messageQueue = new Array();
	this.loggedin = false;

	if (!module.exports.User.id) {
		module.exports.User.id = 1;
	}

	this.id = module.exports.User.id++;

	this.addMessage = function (msg) {
		if (!this.loggedin) {
			return;
		}

		messageQueue.push(msg);
	}

	this.toString = function () {
		return this.name;
	}

	this.normalized = function () {
		return this.name.replace(/[^a-zA-Z0-9]+/g,'_').toLowerCase();
	}

	this.toJSON = function () {
		return {
			name: this.name,
			id: this.id
		};
	}

	this.readMessages = function() {
		return messageQueue;
	}

	this.messages = function() {
		if (!this.loggedin) {
			return new Array(new Command('do_login'));
		}

		if (!messageQueue.length) {
			return messageQueue;
		}

		var tempQueue = messageQueue;
		messageQueue = new Array();
		return tempQueue;
	}
}