Smash TV was always best with two players -- like Guantlet you could work together, watch each other's backs, divide and conquer, and fight over the weapons and prizes. And it ate less of my quarters when someone else was helping.
I'm bummed that I only have two sticks on my cab because multiplayer isn't really an option. Although I suppose I could use a USB dual-shock pad's analog controls for P2.
-pmc