Prototypes are definitely fun to study, it's unfortunate that in the modern age it's mostly overrun with angry japanese who buy games from lots in JP just so westerners don't get them, then sit on them, or how there are groups in the west that will bid to privately collect and only share amongst a small circle. There have been many a story of james bond level heists for arcade board cloning at expos and events, but my favorite being Akka Arrh, where someone posing as a repair tech specializing in "Atari era arcade hardware" showed up to a house call for a private collector, cloned the board while doing repair on another cab while left unattended, and uploaded it publicly later on and now everyone can play it, even if they don't live in the like 5 city radius the cabs got brought out to. Now, whether it's real or not is a whole other spectacle, some say one of the collectors had a grinch moment and uploaded it himself, but we'll never know.