WORM_FBOUND.B is currently spreading in-the-wild. This mass-mailing worm sends itself to all email addresses listed in the infected user's Windows Address Book (WAB). It arrives in an email with a subject line randomly chosen from a group of 17 Japanese language phrases, if the email address of the target recipient ends with .jp.

The details of the email it arrives with may be as follows:

Subject: Important <or random Japanese phrase>
Message Body: <blank>
Attachment: PATCH.EXE

I've heard a WORM_FBOUND.C is floating around through the email systems too.