https://wiki.mozilla.org/Labs/Ubiquity/Latest_Ubiquity_User_Tutorial

“Ubiquity is an experimental Firefox extension that gives you a powerful new way to interact with the Web. Ubiquity commands can do nearly anything. Ubiquity comes with a set of commands that make common Web tasks faster and easier. In this tutorial we’ll teach you how to use some of them. By the end of this tutorial you’ll be able to perform quick Wikipedia, Google, definition, and Yelp searches; add maps to your email; and translate a snippet of a web page, highlight a word, and then email it to a friend.”