The IETF standard for Instant Messaging, still trying to make it in the real world.
Resources:
- Locus, an experimental social interface with oodles of relationship visualization options (and Bayesian classification of your buddies).
- msn2jabber, a SOCKS proxy that allows MSN clients to talk to a Jabber server.
- Jabber.org
- jabberpy - for Python
- MIDP Clients:
- MGTalk - Google/Talk-enabled.
- client source
- mobber