LW.Org offers a Public jabber/xmpp service, after you registered an account you can access it through your own client by pointing it to lightwitch.org.
lightwitch.org is running on Metronome IM an opensource lightweight xmpp server written in Lua based on Prosody, compliant with latest XMPP RFCs (6120-6121)
- Enforces using secured connections for both client and server streams
- Supports a wide amount of extensions, including: Stream Management, BOSH, MAM etc.
- Support of Microblogging using PubSub
- Support of MUC