Modders have managed to create a fully-operational Mortal Kombat 2 arcade cab into a Doom multiplayer map. The cab runs the SNES version of Probe's brawler, so if you just want to play that instead of shooting each other stupid then you can.
The mod is being developed by Cristian Fabian Munoz Isla and is said to be 50% complete. We'll have more as it happens. Thanks to redield21 for the clip.