This is the ultimate ad and content blocker, it's super flexible and powerful. The standard default settings are super effective, and using Advanced Mode allows for some really awesome fine-tuning of the content and domains that are accessed and loaded.

One of my favorite features are the custom lists - in particular, the "annoyances" lists are extremely nice because they block all sorts of obnoxious pop-ups. This is the #1 extension that I immediately download on any browser I use!