These were once used to pirate music but now some no longer exist and some have turned there ways to being more legit.
- Kazaa ( They stopped development)
- Napster (Merged with Rhapsody)
- Limewire (Closed and seized in 2010)
- Imesh (Is still running apparently they reached agreement with the RIAA)
- Ares (I question if it’s legit)
- Bearhare (Now for more legit purpose instead of illegal)
Back when music sharing first started most music companies didn’t take much noticed. Napster use to be the best then it was Kazaa and limewire were the top clients in the 90s