If you aren’t already amazed at the computing power that Apple Watch places on your wrist, perhaps you will be when you see it running a full desktop operating system. In the video below, the new wearable boots up Mac OS 7.5.5 in an emulator.

Admittedly Mac OS 7.5.5 is 20 years old now, but nevertheless, this demonstrates just how far technology has come in that time. When the software was first made available, it required a fairly powerful (at the time) Mac powered by a PowerPC processor — now it runs on your wrist.

The video was put together by software developer Nick Lee, who used the Mini vMac Macintosh emulator on the latest watchOS 2 beta.

You’ll notice it takes some time for Mac OS to boot up on the Apple Watch, and you can’t exactly do a lot with it — not that you’d want to on such a tiny display. But it’s an incredibly cool achievement that’s sure to please the geek inside you — especially if you once used Mac OS 7.5.5.