Just been to help someone with an infected PC - Virut and Thermida were the main problems. I carry a USB Pen Dive with various bits and pieces to help remove these things. I only copied stuff off the Pen Drive and onto the PC but now a lot of those files on the Pen Drive are infected with the Virut virus! Fortunately NOD32 picked it up and I've now formatted the drive. How was it able to do that?