A friend of mine just sent this link to me, I thought it was kind of interesting so I would share

http://securityresponse.symantec.com...grat.3344.html

here's a cut/paste if you don't want to click the link.

W64.Rugrat.3344 is a direct-action infector (it exits memory after execution) of IA64 Windows Portable Executable (PE) files - this includes most Windows applications - excluding .dlls. It infects files that are in the same folder as the virus and in all subfolders. It is the first known virus for 64-bit Windows, and it uses the Thread Local Storage structures to execute the viral code. This is an unusual method of executing code. It does not infect 32-bit Portable Executable files, and it will not run on 32-bit Windows platforms. The virus is written in IA64 assembly code.


Note: A true 64 bit machine is not required for this virus, as it can be run on a 32 bit machine using 64 bit simulation software.

And so it begins.