For several years starting in 2010 I ran my personal website off a Pentium III Thinkpad running Plan 9 sitting on the floor behind my desk. I wrote the web server in Go; it was a "hybrid" in that it served mostly static files, but in the blog subdirectory it would render Markdown to HTML.

It worked great! I eventually migrated to a VPS when the hardware started to get too flaky with age (and years of accumulated dust sucked through the fan inlet)