Panda Security Warns of Massive Facebook Scareware Scam
A fake virus warning is being distributed via e-mail.
The unsolicited warning asks users if their Facebook has "been running slow lately" and tells them to click on their Settings link to see if there's something called "unnamed app" in their application settings. They are then told to delete this nonexistent "unnamed app" because it's an internal spybot.
Facebook says the issue has been resolved.