jQuery plugin for shift + click to select multiple checkboxes (https://gist.github.com/AndrewRayCode/3784055 modified for live collections support)

shift-selectable.js

// usage: $('.container').shiftSelectable() to select all checkboxes in container $('.cont')
// or $('.container').shiftSelectable({items: '.shift-selectable'}) to select only checkboxes with shift-selectable class
$.fn.shiftSelectable = function(config) {
    config = $.extend({
        items: 'input[type="checkbox"]'
    }, config);
    var $container = this;
    var lastChecked;

    $container.on('click', config.items, function(evt) {
        if(!lastChecked) {
            lastChecked = this;
            return;
        }

        var $boxes = $container.find(config.items);

        if(evt.shiftKey) {
            var start = $boxes.index(this),
                end = $boxes.index(lastChecked);
            $boxes.slice(Math.min(start, end), Math.max(start, end) + 1)
                .attr('checked', lastChecked.checked)
                .trigger('change');
        }

        lastChecked = this;
    });
};