Fixoncloud!

Stack Exchange is a fast-growing network of 84 [and counting] question and answer sites on diverse topics from software programming to cooking to photography and gaming. We are an expert knowledge exchange: a place where physics researchers can ask each other about quantum entanglement, computer programmers can ask about JavaScript date formats, and photographers can share knowledge about taking great pictures in the snow.

Quora.com is a question/answer service allowing users to pose questions that other users can answer, each question and answer can have comments, each users can write one individual answer and there can be a summary answer.Each user can choose a description explaining their area of expertise or questions and answers can be anonymous.Questions and answers are searchable.

Slant is a collaboratively edited resource that helps you quickly make decisions.

Super User, part of Stack Exchange , is a Q&A site for computer enthusiasts that's free. Free to ask questions, free to answer questions, free to read, free to index, built with plain old HTML, no fake rot13 text on the home page, no scammy google-cloaking tactics, no salespeople, no JavaScript windows dropping down in front of the answer asking for $12.95 to go away. You can register if you want to collect karma and win valuable flair that will appear next to your name, but otherwise, it's just free. And fast. Very, very fast. »

A Q&A site helps an online community to share knowledge. No matter what your area of interest, people with questions can get super answers fast. Question2Answer is a popular Q&A solution.

Server Fault is a Q&A site for system administrators and IT professionals that's free. Free to ask questions, free to answer questions, free to read, free to index, built with plain old HTML, no fake rot13 text on the home page, no scammy google-cloaking tactics, no salespeople, no JavaScript windows dropping down in front of the answer asking for $12.95 to go away. You can register if you want to collect karma and win valuable flair that will appear next to your name, but otherwise, it's just free. And fast. Very, very fast. »

Startups get your queries answered by the World's Top Investors and Entrepreneurs. Startups + Investors +Entrepreneurs Connect.

Askbot is a Q&A system, like StackOverflow, Yahoo Answers and some others. Askbot is based on code of CNPROG, originally created by Mike Chen and Sailing Cai and some code written for OSQA.

Yahoo! Answers is a way to find and share information. You can ask questions on any topic, get answers from real people, and share your insights and experience.

Bitfortip offers a unique use case thanks to Bitcoin.

Coordino allows you to create a question and answer system for you and your users to enjoy.

Answers.com: Wiki Q&A combined with free online dictionary, thesaurus, and encyclopedias. Ask questions, get answers.

Curositi is a caring and supporting community of people who are eager to learn things. It provides an environment that offers opportunities to communicate new knowledge and solve problems through collaboration with experts and other members of curositi.Curositi helps individuals to engage in a meaningful inquiry based learning that has genuine value. We are encouraging individuals to invest in learning things which they truly care about and make it a habit, rather than viewing it as an activity forced upon them. »