The PHP version of Twitter is open source
Identi.ca is a micro-blogging service based on the Free Software Laconica tool.
If you register for an account, you can post small text notices about yourself, where you are what you’re doing, or practically anything you want. You can also subscribe to the notices of your friends, or other people you’re interested in, and follow them on the Web or in an RSS feed.
The PHP open source community welcomes the new Twitter.
