F-Secure, a mobile security firm, has detected a virus for Symbian called SymbOS/Cardtrap.A that has the unique twist of also infecting PCs. The Cardtrap.A installs Windows worms Win32/Padobot.Z and Win32/Rays to the phone memory card so that if you connect it to your computer it will become infected.
So far mobile viruses have stayed in the mobile world, this is the first hybrid we've heard of.