Arguably the best Pop-up stopper on the internet. This tiny little application sits quitely in your system tray, and when a popup is about to be opened, it prevents it, marking the destruction of the window with a blink of an X in the tray. It's nice to see when it is and when it isn't blocking the popups. The program is freeware, so you won't have any annoying ads, or trial versions to hassle with. The download is a tidy 442 kilobytes, and the full install is less than a meg.
The glory of surfing through Tripod and other free sites is incredible. No longer will you cringe as you load up a fortunecity homepage, waiting for the animated Casino ads, or the scrolling Flash for the Tiny Wireless Camera. It uses little to no memory up if you just leave it running in your tray, and let it start up with Windows. It even combats the popups in programs like KaZaA.
Sometimes you need to have popups too, for links that open in a new window. All you had to do in this case is hold down the CTRL key while you click the link, and Pop-up Stopper will allow it. And when you install it, be sure to check off "Enable agressive pop-up control" in the preferences, otherwise it won't work very well.
Pop-up Stopper is for all versions of Windows, (except 3.1, quit living in the past.) works with Internet Explorer and Netscape, and is available for download at http://www.panicware.com/popupstopper.html.