http://www.snopes.com/computer/virus/postcard.asp
I checked with Norton Anti-Virus, and they are gearing up for this virus!
I checked Snopes (URL above:), and it is for real!!
You should be alert during the next few days. Do not open any message with an attachment entitled 'POSTCARD FROM HALLMARK,' regardless of who sent it to you. It is a virus which opens A POSTCARD IMAGE, which 'burns' the whole hard disc C of your computer. This virus will be received from someone who has your e-mail address in his/her contact list. This is the reason why you need to send this e-mail to all your contacts.
If you receive a mail called' POSTCARD,' even though sent to you by a friend, do not open it! Shut down your computer immediately.
This is the worst virus announced by CNN. It has been classified by Microsoft as the most destructive virus ever. This virus was discovered by McAfee yesterday, and there is no repair yet for this kind of virus. This virus simply destroys the Zero Sector of the Hard Disc, where the vital information is kept.