RPCS3 is a PlayStation 3 (PS3) and PS Vita emulator that is in very early development. Currently usable only for light homebrew and a very small number of commercial games, with heavy glitches. It aims to one day eventually emulate the PS3 fully. Recent efforts have allowed it to also begin emulating the PS Vita in a basic manner; do note that no games are currently playable however.
Development of RPCS3 is early, but promising. As of 22 Mar 2014, it can play the intros to some games with sound. It can also play some of Disgaea 3 and The Guided Fate Paradox, but with heavy graphical glitches and no sprites.
Even on a relatively modern machine, it gets very low framerate on most games. Gameplay usually averages 10-20 frames per second depending on game.
It will be a while before it can play complex PS3 games. The team is small and progress will likely be slow.
As of 2017, RPCS3 can be supported via patreon subscription donations: https://www.patreon.com/Nekotekina