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.
TwitterGadget is a clean, robust, web 2.0 style client for Twitter.com, designed to submit status updates to Twitter via your iGoogle homepage or Gmail Account.