I lied. A quick google search reveals that it's especially common in Thailand (Seriously, what ISN'T common there?)
They're bred with much shorter fins than the ones we usually see so they're a lot faster. Check out www.fighterbetta.com
to see some pictures of how they look. The site is pretty badly translated in places.
There are also quite a few youtube videos of dumb kids doing it, but just for fun like I said before, seemingly not too seriously.
I won't share any links. Probably not something you'd want to see.