It may not be vintage but my 2011 Mac Mini is operational. As a music server it is great with iTunes and my old iPods.
This morning I installed the Powerfox browser along with Firefox ESR and both work excellent. Even plays YouTube videos. Installed uBlock Origin, Proton Pass and some other privacy extensions in ESR. Unfortunately Powerfox is limited with add-ons, but it's quick on this old Mac with 8GB running 10.13.6 High Sierra.
It feels like I'm back in 2011 listening to music browsing the web and converting FLAC files to ALAC with XLD for iTunes.