There are over 18 million songs that you can listen to on your Playstation devices with Music Unlimited
there are more songs coming to the service and they are classic videogame soundtracks. Pretty cool! Right now some soundtracks include Assassins Creed, Silent Hill, Prince Of Persia, Final Fantasy and Castlevania: Symphony of the Night. New songs and soundtracks will be added weekly to the service.
Other requested genres are making their debut soon on the service as well in the coming weeks including Old School Hip-Hop and New Wave. The service also saw a HUGE bump in plays for songs and artists featured at the Grammy awards. The Lumineers, Frank Ocean, Rihanna and others.
If you don't have a subscription you can sign up for a free 60 day trial and if you don't have the service make sure you download it on the PS3 and PS Vita.