1.   Computer glitches could knock out school crossing lights, shut down school heaters and disable classroom computers.

2.   The cable disabled a computer that controls the position of the Mir and the space station started to drift, Culbertson said.

3.   Clinton noted that the virus, which spread by electronic mail, disabled computers worldwide earlier this month and did millions of dollars in damage.

4.   If computers are disabled, US forces could be hampered in their ability to fly warplanes, detect enemy fire or issue commands.