[4] Laconica (pronounced "luh-KAWN-ih-kuh") is a Free and Open Source microblogging platform.
It helps people in a community, company or group to exchange short (140 character) messages over the Web. Users can choose which people to "follow" and receive only their friends' or colleagues' status messages. It provides a similar service to sites like Twitter, Jaiku, and Plurk.
This is definitely an option for those of you looking into corporate micro blogging ;)
Try it out on-line at: http://identi.ca/ [5]
or download you own copy at: http://laconi.ca/trac/ [6]
Links:
[1] http://pulse.veltsos.com/category/it/blogging
[2] http://pulse.veltsos.com/category/it/software/foss
[3] http://pulse.veltsos.com/category/it/open-source-foss
[4] http://linux.philosweb.com/drupal5/files/identi_ca_2.jpg
[5] http://identi.ca/
[6] http://laconi.ca/trac/