Winches..

[Krandall]

CRIPES!!!
Cool idea.. don't know if I'd lift my quad w/ it though...
http://www.youtube.com/watch?v=135zkGk2fak&feature=player_embedded

[disco]

Wow, the cool idea is the pulley on the rack.  I was wondering how he was going to keep from skidding sideways until I saw that.  I've heard of doing this with dual wheel trucks with the holes in the wheels.  Hook your chain in a wheel hole between the duals but I'd imagine it would require a locker because as soon as it starts loading up the other wheel is going to spin.