Saw something a little unusual at a local restraunt - generic cabaret style cab, vertical monitor, single 4-way microswitch joystick with two buttons on either side (unlabeled) and two buttons on the front of the CP.
The weird thing is the two front buttons swapped between "Super Zola Pac Gal" (right button) and Galaga (left button). The swap was instantaeous, and could be done even during the game! (It also didn't share credits between the games.) It was like it had some strange kind of JAMMA KVM switch.