Meebo.com www.meebo.com (Web)
This polished Web app aggregates your AOL, Gmail, ICQ, Jabber, Windows, and Yahoo! buddy lists into a single, Web-based instant-messaging and chatroom experience. Meebo is building in extras, such as games you can play with IM buddies, as well as video and audio chat you’d fi nd with your regular IM client software.
Pidgin www.pidgin.im (Windows | Linux)
Open source tackles instant messaging in this client, which supports more IM networks than you’ve ever heard of.
Trillian www.ceruleanstudios.com (Windows)
Access all your IM accounts (AIM, ICQ, Windows Messenger, Yahoo!, and more) from a single interface that also logs all your conversations, if you desire.