I've had an arcade cabinet with a 9-year old computer in it that finally failed the other day. I tried the Rasberry Pi route awhile ago, it does fine on the oldest 80's MAME games, but has issues with most of the 90's era games of which I'm still quite fond. And as others have noted, it's prolly going to suck for NES/SNES emulation.
So when the arcade computer failed, I tried a different route. I realized my main desktop computer (a Core i7-4790k) is plenty powerful to do some arcade gaming on the side. A long VGA/USB/audio cable later, and my arcade is now running directly off a VM from my desktop. This works so much better than dealing with moving games on/off a SD card, and managing more physical things. It's easy to manage the VM, snapshot it, and change the config without even touching the arcade now.
With VT-d, PCI-passthrough, and the ridiculous amount of CPU cores everything comes with that this should be a more normal thing in the future. It'd be lovely to use those new multi-Gbit wireless standards instead of a cable though...
So when the arcade computer failed, I tried a different route. I realized my main desktop computer (a Core i7-4790k) is plenty powerful to do some arcade gaming on the side. A long VGA/USB/audio cable later, and my arcade is now running directly off a VM from my desktop. This works so much better than dealing with moving games on/off a SD card, and managing more physical things. It's easy to manage the VM, snapshot it, and change the config without even touching the arcade now.
With VT-d, PCI-passthrough, and the ridiculous amount of CPU cores everything comes with that this should be a more normal thing in the future. It'd be lovely to use those new multi-Gbit wireless standards instead of a cable though...