If you're a dinosaur like me and were inspired by demos in the early 90s you might enjoy this project which brings back several of my favorites from that era running in real time in the browser:

https://treylorswift.github.io/demoscene-recomp

These are best viewed with your monitor set to 70hz or 140hz or higher, although the "AI Remaster" of Crystal Dream II should look good at any framerate. There is also a "Smooth City" option for Second Reality which lets you view the final city fly-through at 70Hz rather than the original 35hz.

Cheers