If you've gotten an email recently from a "Uk-Exhibitionist.com" email address with little or no text, and an attachment with the extension scr/pif/bat/exe, it's the klez virus. The sender's address in the From header is faked. Dont believe me?...then check the full mail headers and you will see im right.
Wired has a couple good articles on the klez virus, here and here. You should check them out.
