Doom Has Been Turned Into A Playable GIF, Apparently
A software engineer has ported Doom to a playable gif hosted at a popular fanfiction archive, and it works, though you probably aren't going to be slaying any Cyberdemons with it anytime soon.
Doom is now playable through a GIF image hosted at fanfiction site Archive of Our Own (aka AO3), which is quite the achievement. A software engineer named Andrew Sillers exploited the way that GIF images are loaded by websites like AO3 in order to add new frames to the end of a "looping" image, meaning that you can essentially stream a game or animation as a GIF.