Open Microblogging for Open Source Professionals

I like Twitter, but I feel rather guilty about using it, since it's hardly open source. Of course, there's Laconi.ca, which is not only open source, but allows all kinds of other services to be built upon it. Here's a good example:

FLOSS.PRO is a micro-blogging service based on the Free Software Laconica tool.

FLOSS.PRO is there for people involved in FLOSS, join the groups or create the ones you need. It's built so that FLOSS Professionals can get help and to help.

As you can see, FLOSS.PRO is not only open source, but devoted to the world of open source. Gaining critical mass is the central issue for these services, which is why I still use Twitter, to my shame.... (Via Tectonic.)