Can you play games with more then one person?

[OMG_LOL]

Like smash bros. can you play 2-4 players somehow?

[Iconoclast]

You can usually disable or enable controllers one, two, three, and four and set unused keyboard controls to emulation of their buttons. You can also buy adaptoid devices to use your actual controllers to play the games in emulation.

Some emulators have an internal NetPlay system, but most that support playing online with others use the Kaillera (http://www.kaillera.com/) system.