A friend of mine is giving me a JAMMA cabinet, specifically, a Street Fighter II cabinet (which is actually JAMMA+), but the JAMMA board is dead, as is the CRT. The cabinet itself is presumably in decent enough shape and the remaining hardware presumably works.
I've been wanting to build a MAME cabinet for a long time, so this will save me a ton of work and expense. I already have everything I need to convert it to a functioning MAME cabinet. I have a Raspberry Pi for the brains. It doesn't have enough GPIO pins to wire up all of the Street Fighter II controls without getting a bit fancy (a matrix layout is easy enough, but the software would be a bit more complex), but I can concentrate on player 1's controls initially. I have an LCD monitor that will work nicely with the Pi as well. If I decide I want a CRT, I can pick up an old TV for free off of Craigslist, I'm sure, adding 0 cost, since the Pi can output to that as well ;)
I have a couple of options when it comes to Player 2's controls. I can hack up a USB game pad, or I can hack up a USB keyboard. Either will work, but there are some known issues with hacking keyboards for use in arcade cabinets. I imagine I should be able to find either for fairly cheap, adding very little, if any, cost to the project.
I also plan on loading Quake onto the Pi, as I have been dying to play is with arcade controls forever.
If I do this right, maybe spending a few bucks on connectors, I should be able to do these mods and make them completely reversible, should I later decide to restore the cabinet to its former glory. Regardless, once I have the cabinet (in a couple of weeks), I'll post pictures, along with a progress report on my conversion.