Try the weird search!
Radiooooo is a database that is collecting popular music from across the global from different eras that allows you to search by decade and region to discover new tunes. You can specify whether you’re looking for slow, fast, weird or any combination of the three.
The site is still in beta and not all categories are completely populated yet, but they are crowd-sourcing and you suggest tunes for an unspecified reward (after site-vetting).
Check out Messer Chups’ ‘Good Night’, a slow, weird tune popular in Russia in the 2000s, below for a taste of what kind of odd gems you can discover.