Answers.com is a revolutionary Answer Engine: a one-click reference library on demand. With 1-Click Answers software, just click on any word (Command+Option+G) in any application (e-mail, browser, Office, and so on), and get a quick definition or explanation--instant answers from encyclopedias, biographies, celebrities, companies, news, sports, weather, stock prices, maps, military terms, idioms, tech terms, acronyms. Unlike search engines that show you long lists of links to follow one-by-one, Answers.com brings you organized information from over 100 content sources in a simple pop-up window, without interrupting your work. The Answers Widget is also availalbe to give you quick access to the content of Answers.com directly on your dashboard. It is available as a separate download. Windows version also available.
Requires OS X 10.2 or higher and Safari