(copied from my Slashdot posting)
W64.RugRat.3344 has been released as a proof of concept virus. It is the first virus which will only run on Windows on the IA64 platform, and uses APIs from 3 native DLLs to avoid crashing applications. It infects files that are in the same folder as the virus and in all subfolders. The author of the virus has also written other concept viruses* in the past.
* Corrected from virii, which people were nitpicking over on /.