by Gaim
I guess I wasn't hip enough to know about one of the most popular new messengers. I had to be told about Gaim.

Gaim supports old accounts on AIM, ICQ, IRC, Napster, MSN, Jabber, Yahoo!, Gadu-Gadu and GroupWise. This means you can use an existing account from any of these programs, and it will even load up your existing buddylist.

One thing that caught my eye was the tabs. I could easily switch between one conversation to another using tabs instead of having multiple windows taking up space on the desktop.

The makers of Gaim are smart enough to add a lot of the configurations that each of the messenger programs have. For example, I can see the profile pictures from Yahoo right on the buddy list. As well, those weird symbols people add in their name for MSN Messenger are taken care of with some settings.

This program is sure to compete with other multi-messenger programs such as Trillian. Gaim has an advantage because it supports a wider group of operating systems and platforms, not to mention that Gaim is open source.