POP UP MALWARE

Dirty tricks
Imagine this: You visit a website and up pops a message, "Your computer is not secure -- click here for a free spyware scan." Anxious, if not alarmed, you click the link. You approve a "small download", the program starts, and you're told you have 87 spyware programs on your computer.
Little do you know that it's a scammer's dirty trick -- the download included spyware that now reports everything you do on your computer, including account numbers and passwords that you enter. To top it off, there is an offer to remove the 87 infected items for just $39.95. That's just one example of the kind of scams you run into on the Internet these days.
Blocking popups
Just clicking the "No" button, or even the "X" in the upper-right corner of some popups can trigger an attack. The easiest and safest way to close unwanted popups is by using "Ctrl-W". [Hold down the "Ctrl" key and then press the "W" key]. That should close the popup safely. The best thing to do is block them in the first place though. :-)
The Firefox popup blocker does a superb job blocking undesired popups. It also allows the ones you want in response to links that you click. The latest version of Internet Explorer in SP2 for Windows XP does nearly as well as Firefox. Pop-Up Sentry is a very effective stand-alone popup blocker.
More online
Test your popup blocker, as well as find links to free popup software. (Which you won't need if you switch to Firefox.) If you like to play, turn off your popup blocker and experience how bad popups can be. The tests are brought to you by WebAttack -- now called SnapFiles.
PC Today has a comprehensive and easy to read report on popup blockers, including the blockers that are included in Firefox and Internet Explorer.