Xfire

Xfire is a free gaming tool that automatically keeps track of when and where gamers are playing PC games online and lets your friends see what you're playing and join you in your game. It doesn't matter what service, server, or game that you're playing. It keeps track of all this for you, making keeping track of friends and joining in their games all the easier. It also serves as a chat program like AIM or ICQ. Lastly, it also has a basic file-downloading component where you can get demos and patches for certain games in addition to fan films or trailers. This program is HIGHLY recommended for RS members to download.

Of interest, Viacom (owner of MTV) bought out Xfire on April 24th, 2006 for $102 million.

• ...And you can grab it right here
• List of RSers' Xfire usernames