Wikipedia Search allows you to type the word 'wiki' into your browser's search bar, press the space key, and search for an article on Wikipedia. You can also select any word or phrase on the web, right-click, and search it in Wikipedia. If you have Awesome New Tab Page installed, there's even a widget for that built-in.
The WOT add-on is a crowd-sourced enhancement to your browser protection
It is a browser add-on which lets you search via your favorite search engine
