1.   Billions of junk e-mail messages are delivered annually, according to e-mail experts.

2.   He got the program, he said, so sites could not target him for junk e-mail messages.

3.   The last is easiest to abandon if junk e-mail messages become intolerable.

4.   Typically, such junk messages tout get-rich-quick schemes, fast weight-loss programs, pornography and gambling opportunities.

5.   In addition to the hailstorm of junk messages slowing down Internet access around infected computers, it can overwrite critical Microsoft Windows system files.