GAIM, the great instant-messaging program that handles your IM needs for not just a single service but for Yahoo!, AOL, Google, MSN, ICQ, IRC and even more stuff that I've never heard of is CHANGING ITS NAME.
I got the news from Desktop Linux, which gives the back-story -- the program used to be called GTK + AOL Messenger and, when AOL got squirrelly about it, chenged its name to GAIM . Now that AOL is pushing its IM product as AIM, that squirrelliness has returned, and the open-source project is renaming itself Pidgin.
I've used GAIM under Linux, and it works very well -- I can send IMs to Yahoo! Messenger accounts without all the ancillary crap, like that opening news page and all the other plug-ins I don't need. And since it also works with AOL, Google and MSN's IM services, you can replace a bunch of separate, incompatible programs with a single one that works on all platforms.
For the detailed history of the GAIM-to-Pidgin transition, go to the program's own site, read all about it and download the current version. The new Pidgin 2.0.0 is expected within the week.
GAIM (and soon-to-be Pidgin) works on Linux, BSD and Windows. It will run on Mac OS, but only if you have X server and GTK+ installed, and unless you're obsessed with running Linux-style apps on your Mac, you probably don't (and won't). But you just might want to, because having one IM program for multiple services is an idea who's time hasn't just come -- it's time is here.
Note: The image above is the ex-GAIM, now-Pidgin logo.