Though it's a bust as a pop-up squasher, this Internet Explorer-only ad blocker is decent at foiling Flash. In our tests, Pop Up Blocker Pro Rich Media Ads Edition let most pop-ups through. In the Stop 100% mode, it blocked all new Internet Explorer windows, even ones we opened ourselves. However, it did a fine job squashing Flash ads and banners. An ugly floating toolbar and a system-tray icon provide access to program settings and additional privacy features. The latter can not only delete your browser cache, history, and cookies, but it also can erase index.dat files with your personal information (usually impossible without restarting the system). They also can clean out Windows Recent files, temporary folders, and RealPlayer's recent files. However, we were puzzled at having to close all browser windows to execute these features. Given its mixed ad-blocking abilities, we'd use this program alongside more effective anti-pop-up software.