noscript

NoScript is a great Firefox extension that lets you hand-pick which web sites to be allowed to use JavaScript, Java, and Flash. You can surf online safer and faster(because of fewer JavaScripts running).

Another cool thing about it is that by looking at what domains NoScript allows and blocks(right-click on the "S" icon), you get an idea of what kind of services a website uses. BTW, you can just look at the HTML page source codes to find out what JavaScripts are loaded if you have too much time.

For example, you can see my site loads JavaScripts from "google-analytics.com","performancing.com", "crazyegg.com"(all 3 are web analytics services), "meebo.com"(the Meebo chat widget).

Tags: firefox extension javascript noscript