Answers.com is an online information portal that has a collection of over "4 million answers that are are drawn from over 120 titles of brand-name publishers, the Answers.com editorial team, Wikipedia and user-generated answers."
Answers.com can be launched from Internet Explorer, Firefox and Opera browsers.
The unique thing about Answers.com is that it goes beyond the search box and offers free software that a user can download (Windows only) and when you alt + click on any word in any program on your screen.....a pop-up windows appears with an AnswerTip. Read more information on this application here.
Answers.com teacher toolkit is a great reference and search option for teachers and students. Answer.com teacher toolkit was the Winner of the 2006 Codie Award for Best Education Reference or Search Service.
This portal starts with a lot of links that would interest educators such as: lesson plan tools, free worksheets & posters, free downloads, ESL, Education Blogs, Librarian Lowdown, just to mention a few.
Take Answers.com for a spin and give it a try!