Cluztr

Cluztr takes it to the web by tracking every site you visit online through your browser. Not only that, it also keeps a history log or “clickstream” of all those sites. One word of advice, avoid visiting sites that your mother would not think much of, as it’s all out there for your friends to view. Cluztr installs a plug-in to your FireFox or Flock browser (sorry IE and Safari users, Cluztr is hopeful for a mid to late 2007 release) where it then captures your entire web surfing history and compiles it into your “clickstream” which you are free to share or publish on the web for all your friends to see. There are also social functions built into the sidebar which allow for posting of messages for that specific site which other users can see when visiting that same site.
For more :http://www.cluztr.com/
(Via)-Mashable