It is important to keep some necessary program away from your hard disk. You can keep them in a CD-Rom, DVD or USB stick.
Anti-virus progam should be one of them. We will introduce you a virus cleaner which can be kept in USB disk.
avast! Virus Cleaner is a useful tiny tool that can be kept and running from your USB stick.
avast! Virus Cleaner is a free tool that will help you remove selected virus & worm infections from your computer and also performs necessary fixes to your system registry, Startup Folder etc. if needed.
The program can also deactivate the virus present in memory. avast! Virus Cleaner is currently able to identify and remove the following worm families: MyDoom and Beagle/Bagle,Badtrans, BugBear including B variant, Nimda, Opas (aka Opasoft, Opaserv), Sircam, Sobig including B, C and D variants, Yaha (aka Lentin), and others.
You can find this virus cleaner from following URL