I like going around checking for some bjj moves to try out in my basement. Normally I like looking variations of a move rather then just a 20 sec clip of a move.
Either way, I came across this technique called the sitting mount and actually tried it a few times. Its not bad getting the set up, but pulling off the submission takes a little bit of practice
Its a 5 min video of Keith Owen from bjjmoves.com.
[edit: I'm a newb at adding youtube vids, it didn't work so heres a link instead.] http://www.youtube.com/watch?v=cviTDQqYYkQ