Identi.ca is a micro-blogging service. You can use it to write short notices about yourself, where you are, and what you're doing, and those notices will be sent to all your friends and fans. Identi.ca is different from Twitter, in that Identi.ca is an Open Network Service. Their main goal is to provide a fair and transparent service that preserves users' autonomy. In particular, all the software used for Identi.ca is Free Software, and all the data is available under the Creative Commons Attribution 3.0 license, making it Open Data. The software also implements the OpenMicroBlogging protocol, meaning that you can have friends on other microblogging services that can receive your notices. If you don't like how Identi.ca works, you can take your data and the source code and set up your own server (or move your account to another one).