This fish is part of a long term project. You can see him swim a little here: http://www.youtube.com/musetavern. I put the rig together as part of class at RISD. The whole thing should be done May of 2008.

Anyhoo...I lit the room just like some of my other images here. Some high ambient geometry around the bottom edges of the walls, wth three more pieces from above, and rendered with Final Gather. Then I did a spherical render of the room, and used that for IBL and final gather on the fish. It worked pretty well. There's still some noise in the shadows of the animation, but those kinks should be worked out eventually.