MICHAEL JACKSON VIRUS: Hard to identify because it is constantly altering its appearance. The virus won't harm your PC, but it will trash your car.

CONGRESSIONAL VIRUS: The computer locks up, screen splits erratically with a message appearing on each half blaming the other side for the problem.

AIRLINE VIRUS: You're in Dallas, but your data is in Singapore.

PBS VIRUS: Your PC stops every few minutes to ask for money.