You don't have much to worry about viruses through small objects such as PDA and CELL are alot like the sneaker net days.... back in the the old days where viruses mostly came from floppies that were passed to evil peaple. As long as you make sure nobody can pick up any signals or you keep your PDA away from your PC you should be ok. As for cell phones.... there is still the threat of SMS bombs and cloning but you'll hardly see anyone bored enought to do any of this unless you piss someone off.