This thing looks really cool. It's kindda like the all in one atari controller combo, but with nintendo games and the ability for 2 players and a light gun. I picked one up at the mall the other day but haven't gotten around to playing it yet. With super mario bros, contra, duckhunt and about 70 other games I had to get one! There is also a port to plug nintendo cartriges in the back of the controller. I think it may only accept the japanese famicom games, but with a cheap $10 converter its a portable nintendo.
Heres some specs
http://www.nesplayer.com/pirates/superjoyiii.htm