SO jQuery Fiddle

Test Fiddle mainly for SO Questions jQuery 1.4.3, UI 1.8.5

by Nick Craver

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.5/themes/ui-lightness/jquery-ui.css">
<div id="selected">
    <ul class="sortable-list">
    </ul>
</div>


<div id="container">
    <ul class="sortable-list">
             <li>1</li>
             <li>2</li>
             <li>3</li>
             <li>4</li>
             <li>5</li>
             <li>6</li>
             <li>7</li>
             <li>8</li>
             <li>9</li>
             <li>10</li>
    </ul>
</div>

CSS

div { border: solid 1px black; }
ul { padding: 20px; }
li { border: solid 1px #ddd; }

JavaScript

$(document).ready(function(){
    $("#container li").draggable({ revert: 'invalid' });
    var total = 0;
    $("#selected ul").droppable({
        drop: function(e, ui) {
            $(ui.draggable).css('position', 'static').appendTo(this);
        },
        accept: function() {
            return $("#selected li").length < 5;
        }
    });
    $("#container ul").droppable({
        drop: function(e, ui) {
            $(ui.draggable).css('position', 'static').appendTo(this);
        }
    });
});