u/cuavas

This works in Chromium-based browsers, and emulates the subset of 16-bit x86 typically used in programs compiled using gcc-ia16 (e.g. it doesn't emulate the carry and overflow flags):

https://github.com/rebane2001/x86CSS

It's a few months old now, and I apologise if this was already posted here. This is a working x86 emulator written entirely in CSS. It just has a small HTML wrapper to allow browsers to load it. By default, it uses a small piece of JavaScript to provide the clock which gives a performance improvement, but you can disable JavaScript and it will fall back to a pure CSS implementation.

This isn't practical, but it's a pretty unique emulator, and I hope some of the people here find it interesting.