jCarousel Lite
Offers a multi-option carousel (slider)
http://www.gmarwaha.com/jquery/jcarousellite/
CSS Globe Tooltip
Dead simple hover hints
http://cssglobe.com/post/1695/easiest-tooltip-and-image-preview-using-jquery
Cycle Lite
Rotates banners/images
http://malsup.com/jquery/cycle/lite/
jQuery Zoom
If you have designs where the details have a lot of importance, you should use this script to let your site’s visitors know that you don’t neglect details in your designs.
http://www.mind-projects.it/projects/jqzoom/
Kwicks
Nifty little effect for menus, can also be used for other things if you are creative (and I am sure you are).
http://www.jeremymartin.name/projects.php?project=kwicks
jQuery Virtual Tour
If you are really proud of your studio, you can give a good feel of what it looks like with this virtual tour jQuery plugin.
http://www.openstudio.fr/jQuery-virtual-tour.html?lang=en