BOOOO. x42. (Read comments below for reasons why this site SUCKS.)

Have you looked at the screenshots yet? Please do so.

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I've never really used Experts Exchange, but as far as I can tell, Stack Overflow is superior in the area of programming. Its sister sites (see www.stackexchange.com ) are probably superior in their areas too. At any rate, they are all free and have fantastic communities.

BOOOO. Biggest site on the net that practices google cloaking. If you look at answers from within their site you can see the answers, if you find them through google they try to get you to pay for a membership first. Stack Overflow is much better for finding answers to difficult programming related questions and has a much stronger and thriving community. They also have a collection of other FAQ sites for other domains (superuser.com for general computing questions, serverfault.com for server admin specific questions, and many more to come that can be found on area51.stackexchange.com).

Site hides the answers to problems which you have to pay to see