Facebook-like elastic textarea

HTML

<script src="http://jquery-elastic.googlecode.com/svn/trunk/jquery.elastic.source.js"></script>
<div id="wrap">
    <textarea class="my-textarea" placeholder="Shift+Enter breaks line, Enter sends form" cols="20" rows="5"></textarea>
</div>

CSS

html{
    background-color: #f5f5f5;
}

#wrap {
    padding: 25px;
}

textarea {
    border: 1px solid black;
    background-color: #fff;
}

JavaScript

$('.my-textarea').keypress(function(e) {
    if (e.keyCode == 13 && !e.shiftKey) {
        e.preventDefault();
        alert('sending comment...');
    }
});

$('.my-textarea').elastic();