the old red brick is pretty decent it depends on what year can on what it does, full live engine data on all round diagnostic plug cars and as the cars get newer more systems can be read, around 96 you can get into the hvac and instrment cluster, most computer controled tranny cars you can atleast read codes and get some data and the later stuff gets more interactive including stuff like activating the vanos and shutting down individual fuel injectors
all america wants is cold beer warm cat and a place to take a poop with a door on it