POPUP TEST provides a free and simple way to test your popup blocker software. The website will put your stopper to the test by launching a series of safe popups using a variety of different methods.
Most of these popups should be blocked if you are using Windows XP with ServicePack 2, as this included a popup blocker for Microsoft Internet Explorer. For added protection you can also install the free Google toolbar.
Other browsers such as Mozilla Firefox, and K-Meleon feature built-in popup blockers. The popup blocker in Firefox is effective, however the K-Meleon one will try to stop all popups, even the ones you want to appear.
Popuptest also features reviews of software designed to stop popups, including many free popup blockers such as Hitware Popup Killer Lite and Smart Popup Blocker.