Fightcade is a matchmaking application for playing retro games online, bundled with different emulators for seamless online play. Free, and without ads!

Fightcade comes with a custom GGPO implementation and other emulator improvements, making it the best platform for rollback-based P2P netplay. This means that demanding games in terms of input lag and responsiveness can be played over the internet with very little perceivable lag.