Annalee Newitz's Techsploitation column talks about a the MoodGrapher, a tool that scans the mood tags in LiveJournal and reports on how the community responds to current events. For example ...

LiveJournal, or LJ ... “Everything was like that,” Fitzpatrick says. “Current mood, current music, profile pics—it was all screwing around and trying to add whatever new things we could ...

About 250,000 new LiveJournal posts are created every ... tries to explain match these blogospheric mood swings to current events. It identifies emotional peaks by comparing recent label usage ...