So events like Free Play Florida (https://www.jrtwine.com/blog/?p=643) highlight the importance of actually having a way to play a game for free. To that end I am thinking of making available some minimally invasive button kits that can quickly be added to a game, to gain the ability to credit the game without opening it up.
These range from basic membrane buttons:

To more tactile buttons:

To my old microcontroller based solution that allows crediting any game1 by chording two, tree, or four inputs (e.g. pressing Down, Fire and 2P at the same time), or by using the joystick portion of the Konami Code (Up, Up, Down, Down, Left, Right, Left, Right):
I think these will make life much easier for both the game owners and the players. Old school gamers will likely love the Konami Code version.
(See theupdated post about these devices.)
1 This means a game that is wired in a standard fashion where its controls are inputs that are pulled to GND when activated. Games that are on emulated platforms that use low-cost “Zero Delay” input boards like these will not work:

