The most common source of virus infection for computers these days is Pen-Drives. This has become a big annoyance.
Useful utility called Ninja-Pendisk.
You simply run it on your computer and will monitor every pen drive you plug in, and remove any potential viruses.
You can simply Download Ninja Pendisk
and run it, it will sit on your system tray, and monitor any pen-drive which u connect to your computer. It works for Windows XP and Windows Vista both.
Also you can set it to start at start-up, so that you need not run it every time you start windows, it will come automatically.
Hope you find it useful, if you have any suggestions or comments, please leave a comment below.