FastestFox (formerly SmarterFox) is one of the more powerful add-ons to enhance Firefox browsing. It displays a clean-looking bubble filled with customizable search engine shortcuts when you highlight a word or phrase. Type a query into the Firefox address bar, and FastestFox will offer up suggestions as you type. It will also place alternative search engine icons on a results page (like Google, Yahoo, and Bing), and will repeat smaller version of those icons on Wikipedia pages, along with a list of related articles. To open a new Web page faster, there's the qLauncher. One hot-key combo brings it up; tapping a single keyboard key opens Facebook, the New York Times, and whatever else you program in.
FastestFox doesn't stop there. Right-click anywhere on the page to separately download all the links, images, and Flash video content on a page. The endlessly useful Endless Pages feature preloads subsequent pages of multipage sites, so that instead of clicking to advance through, you can just scroll down (and down and down.) Equally useful, but not always as consistent, are the copy/paste features (turned off by default) that copy the text you highlight, and will paste it elsewhere with a mouse click.
Not every feature behaves uniformly at all times. The page scroll has been known to be oversensitive or unresponsive at various times. The alternate search engines are limited in some features, and highlighting text hasn't always copied it to the clipboard. Yet the pros vastly outweigh the cons, making FastestFox a must-try add-on for anyone who spends significant time online.