Four excellent sites offering free answers answered by experts. I hope they remain free forever. They can be great tool for research….
1. Yahoo Answers – Great site!
2. Wondir – Ask science questions
3. Ask a Scientist – A good site with answers from real scientists.
4. All Experts – Thanks Akhil Kamma for this link
Hey pal, how about adding http://www.allexperts.com to the list. Its one of the oldest in its business with a focus on not just science and education but possibly any other field we could imagine. Its an amazing site and its free as well.