Open Source Alternatives to big-name IM systems

Geoff McLeod writes:

With all the news recently about AOL v. Microsoft v. everyone
else in the Instant Messaging arena, I just wanted to remind people
to not overlook the Open Source IM systems that are available.
Projects brewing right now include: The WebGuys Instant Message
, Jabber and
and some non-Open Source stuff: Ding! and
Finally, let’s not forget what the IETF is
up to!

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