I was rolling recently and have had some success with this move. but i dont know if it already has a name or where i could look more into it.. so if anyone can tell me where to look that would be great.. here's a link of me doing it. Pretty much just s-gripping behind the neck from guard and pulling down with my elbows..
http://www.youtube.com/watch?v=lg9rRfp40mY
http://www.youtube.com/watch?v=lg9rRfp40mY