The "From" address on the email is not the real computer the email is coming from. It grabs that email address at random from places like email address books, and fakes it as the "From" email address.
Don't open the attachments!
I didn't receive any attachments with mine, as all my email is filtered through www.Spamcop.net - which automatically detects viruses and removes them from the email. It's a pretty good service....
You can read more about this virus at the link below.
- Dien Rice
Sobig worm returns