Storm has been sending out pump and dump spam for quite a while with everything from plain text to images to zips. Now, it's throwing MP3's at us. Here are two files below. So far, the subjects have been blank with "Re:" or "Fwd:".
Of note, the X-Mailer is "Microsoft Outlook Express 6.00.2800.1106" but that varies with each new iteration of storm. I've seen it claim to be Thunderbird in the past.