The newest virus circulating is the UPS Delivery Failure. You will receive
an email from UPS Packet Service along with a packet number. NOTE: The word
packet is misspelled on this line. It will say that they were un-able to
deliver a package sent to you on such and such a date. It then asks you to
print out the invoice copy attached. DON'T TRY TO PRINT THIS. IT LAUNCHES
THE VIRUS!
Snopes confirms that it is real:
http://www.snopes.com/computer/virus/ups.asp