aux.app - A free web-based music platform to play music from other popular online streaming services.
BandNext - Discover bands that sound similar to artists you already love with BandNext. A single click saves your results to a Youtube playlist.
Songlink - Share music with anyone.
Gnoosic - Even if you don't know what you are looking for - gnod will find it.
Openwhyd - Collect and Share the tracks you love.
TasteDive - TasteDive recommends similar music (musicians, bands), movies, TV shows, books, authors and games, based on what you like.