I recently installed this Firefox plugin called PicLens and I'm simply loving it!
What it does sound pretty simple, but looks pretty amazing - click on the bottom left corner of any photo in a photostream on Flickr or Facebook (or any other photo page) and the next instant you see a 3D carousel view of the same!
Yeah you've probably seen it earlier, but the great thing here is it activates it for any darn web view and I don't surf Flickr without PicLens anymore!
Give it a shot - and watch it pimp it up! Also available for IE, Safari and desktop view.