This was a really awesome video a friend showed me. It has wildlife fighting with each other, so don't watch if you don't want to see that sort of thing. This one is pretty unique though, I don't want to spoil it for those that haven't seen it. But it's really very interesting.
http://www.youtube.com/watch?v=LU8DDYz68kM
http://www.youtube.com/watch?v=LU8DDYz68kM