- fully cross-platform - use the same program to do your IM'ing on Windows, Linux, BSD, other Unix, Mac, or whatever else you come across
- supports multiple protocols - use the same program, with a single buddy list, to message buddies on AIM, Yahoo, ICQ, MSN, Jabber, Novell Groupwise, IRC... the list goes on and on
- tabbed conversation windows - keep all of your conversations in the same window and just click tabs to switch between them
- supports easy, hassle-free secure encryption with an optional plugin - note the "Tx: plain Rx: plain" buttons in the screenshot - those indicate / select secure vs. plain text
- incredible conversation logging, organized by buddy and by date and time - see bottom mini-screenshot
- never any worries about spyware or ads or demands for registration or any other crap - it's open source!
You can download GAIM itself here, and if you're interested in the encryption plugin (and you SHOULD be, unless you're comfortable with the idea of bored law enforcement types sniffing your conversations for "interesting" keywords - which you SHOULDN'T be), you can find it here. You may also want to take a look in general at the available-but-not-bundled plugins; in particular I do use the "Extended Preferences" plugin as well as the aforementioned encryption plugin.