General Question and Answer WebsitesYahoo! Answers This free site allows users to ask questions and receive answers from fellow users. Question topics include subjects such as Arts and the Humanities, Science and Mathematics, and Education and Reference. Users receive points based on their answers, and almost all questions receive a quick response. A large number of answerers seem to be from the younger crowd, so be prepared for some silly and irrelevant quips along with the helpful responses.
Google Answers Answerers on this site are paid researchers. You pose a question on any topic and offer to pay anything from $2.50 to $200. Not all questions are answered. However, the answers that are given tend to be well-written and thorough. Most people tend to pose in-depth or hard-to-answer questions and are quite pleased with the response they receive.
Answerology This service allows users to answer each others questions and form Question Groups that track the questions in a particular topic. Questions and Answers tend to be more social than academic.
Academic Question and Answer WebsitesGeneral Academics
About College This service provides answers to questions about college life. Answers are sent by email and may also be posted to the site.
Ask A Librarian Brought to you by the Library of Congress, this nifty service allows you to ask a question and receive an email response from a librarian. As a word of warning, they request that users avoid simply sending in their homework questions. However, this service can be invaluable for specific research questions. Answers are typically received within five business days.
Ask Philosophers Hosted by the University of Amherst, this site allows users to ask a philosophical question and receive a response from a philosopher. Answered questions are posted on the site within a few days.
Ask a Linguist Your linguistic questions can be answered by a panel of professionals on this site. Answers are posted on the website, along with your first name.
Ask a Geologist Questions about the earth are answered on this site by U.S. Geological Survey scientists. Answers are generally received by email within a few days.
Ask Dr. Math Your math questions can be answered and posted as an example on this site.
Go Ask Alice! Hosted by Columbia Universitys health department, this service answers a select number of health-related questions each week.