What is a fun, free online computer game that a player has a network?

Anyone know of some online games that have a role multiplayer network to play friends who do not sit next to you? As a game that does not have to download a fun game for when your bored is quick and easy to play (Ie, pocket tanks – Have not found one that has a network multiplayer though). It may be action or shooting, etc, nothing more than games. Any suggestions?

DarkOrbit – Race through space! Space battles and exciting mission that lead to the top of your business

Computer Girl V1.3 (Moviestorm Machinima)