Lightbox 2 = JS Goodness + Your Image Gallery
Wow, this is a neat tool:
http://www.huddletogether.com/projects/lightbox2/
I slapped something together on my staging server:
http://webstaging.dewey.lib.umn.edu/image/tid/224
It could hardly have been easier. I also love that this gracefully degrades. With Javascript turned off, users are simply taken directly to the image itself. I can imagine a number of uses for this utility, but I'm most interested in looking at integrating it into online exhibits, where we might have an image that triggers a pop-up that allows users to page through various images. This is a common feature on newspaper sites and the like.