Supercade!!!

supercade and ggpo are two great softwares to play online with many arcade games ... mostly from capcom and snk.... both based on final burn I prefer supercade than ggpo....

from supercade site

What is Supercade? Supercade is a lagless P2P (peer-to-peer) arcade game emulator. It currently supports over 150 games, mostly of the fighting genre. A list of all supported games can be found here. It functions as a client and server where all users can interact with each other and issue direct challenges in the games they want to play. Replays are automatically generated and stored on the website (optional). after signup and downloaded their client (all free), google for some romz and PLAY! or watch the latest replay! supercade