http://www.youtube.com/watch?v=LSxnaqRRays&feature=related
Embedding of the video is disabled, but at 1:26, he throws a curious double. It looks like a frontflip to underflip, and then some.
Does it have a name? Or maybe it's one of those antique tricks that no one throws anymore? It's not something I've ever seen, and technically should be quite difficult because of the change in momentum required Either way, it look pretty sick. Enjoy.
Also, it may be a repost. I had no idea what to search for.