First, let me be clear I'm not trying to actually monetize emulated console games, same as I'm not trying to monetize arcade games in MAME. There is no ethical issue to discuss here.
I'm in the process of building a cab with a coin acceptor. I'm doing this to give my 3 year old daughter something to do with her allowance. Ya know, teach her the value of a quarter, the way we learned, and expose her to the classics at the same time. Really, it's just a fancy piggy bank for her...
I'm looking for a way to make a game lock down it's controls until it accepts a coin, cycle through menus, then start the game. I've seen some questionable arcade operators do this with console versions of fighting games.
I'm wondering if there is a flexible system out there for managing control lockout, detecting game over, and tracking coin credits. At a minimum, unlocking controls for a limited time like PlayChoice cabinets would be acceptable.