Cool prank virus which starts when computer boots up

This is a virus that makes a msgboz when the computer boots up and gives you option to format your hard drive. Harmless but gives friends a shock

A funny Fake Virus

A fake a virus, i remember this fake virus when i was in highschool, my teacher doesnt know whats going on to the PC, he cant do anything he really freaks out he call someone but it also doesnt know what to do.. They turn off the pc w/o shutting down