A fan-made port of Super Mario 64 has Nintendo's classic running at 4K resolution on PC.
We've seen plenty of retro games running with improved performance on PC via emulators before - the difference here is that this is a port, put together by fans with access to the game's source code.
Mario 64 is one of a trio of plumber classics getting a re-release for Nintendo Switch later this year - along with other Mario games old and new. Just don't expect the Switch to hit 4K like this.
It's a little surprising to see this video still online after popping up at the weekend - usually these things get pounced on by Nintendo legal ninjas. YouTube channel owner Unreal has said he isn't sharing a download link to the game itself - which is a wise idea.
See the below video, surfaced by VGC, and make sure you crank it up to 4K resolution: