What is a good alternative for Yahoo Answers?

Stack Exchange network consists of 176 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. It covers a vast range of topics and there are some impressively knowledgeable participants. But trolls need not try. They are not countenanced. It is a serious site that will only post serious questions and it encourages serious answers based on research.

Quora and Reddit are Both Great Alternatives to Yahoo Answers give it a Try 

Trying to actually establish a life outside of the Internet might be a good alternative.

answerbag, answermug, similar worlds and quora

I would say "Facebook." It's more interactive.