Botnet fishers
I've had over a dozen spam e-mails today all with attached files to try to infect my PC so that it becomes part of a botnet. All have been "spamcopped".
If you get an "invoice" or a "statement" attached to an e-mail from a firm you've never heard of (or one you've never dealt with), don't open it!
If you've opened one already, your computer is infected and you need help.