The AJAX control toolkit is great, but it's always better to have more tools and controls.
I found a few great sites that have really nice demos and open source javascript code to make your site look cool.
http://orangoo.com/labs/GreyBox/
http://cow.neondragon.net/stuff/reflection/
http://web-graphics.com/mtarchive/001717.php
http://www.ajaxim.com/
http://www.mochikit.com/
Update: To make the Reflector work in IE, you need to add this tag:
<
script type="text/javascript">reflection.style.filter = 'flipv progid:DXImageTransform.Microsoft.Alpha(opacity='+(options['opacity']*100)+', style=1, finishOpacity=0, startx=0, starty=0, finishx=0, finishy='+(options['height']*100)+')';</script>