The number of displays people have ported Doom onto is head spinning: Inkjet Printers, a Commodore 64, ATMs, calculators, iPods, Apple’s Touch Bar, and even a virtual console within the game itself. But it now seems that we’ve reached a whole new level of Doom-on-a-display ingenuity, after someone managed to port Doom 2 to a single keyboard key.

The incredible feat was achieved using the Optimus Maximus keyboard, which was released all the way back in 2007. Each of the device’s 48 x 48 pixel key displays can be programmed to show a sequence of symbols or images, which is how the game appears in the tiny space.

The key itself isn’t actually running the shooter; instead, Redditor AyraA_ch has Doom 2 running on another display that is constantly taking screenshots. These are quickly converted to the right size and format before being played in order on the Maximus' key, making it appear as a video.

Running at 5 – 10 fps means it’s far from smooth, and the lag will no doubt be a problem, but it’s still pretty amazing. The question now is where to we go from here? Is there a display smaller or more unusual left to play Doom on?

While the Optimus Maximus’ customizable keys are fairly cool, the keyboard didn’t prove very popular. Being manufactured by a design company meant it lacked the quality of most PC keyboards. Activating the keys took heavy pressure, the build quality was questionable, and it required an external power source. On top of all that, it cost an incredible $1500. Only a few were ever made, and they are no longer being produced.