MrBoycott.com works like Twitter in a way.
MrBoycott is a free social networking and micro-blogging service that enables it's users to send and read messages known as jabs. Jabs are text-based posts of up to 300 characters displayed on the author's profile webpage. They will also show up on the home page of MrBoycott.com.
Users have their own profile webpage (i.e. mrboycott.com/your username) that displays their latest boycott and protest updates. A user can read another person's profile page and also receive updates from others. In addition, users can become "friends" with one another, or simply be a "follower."