Question2Answer - A Q&A site helps an online community to share knowledge.
Stack Overflow - Community-based Q&A part of the Stack Exchange platform.
Reddit - Reddit gives you the best of the internet in one place. Get a constantly updating feed of breaking news, fun stories, pics, memes, and videos just for you.
The Answer Bank - The Answer Bank is the UK’s leading question-and-answer site.
Quora - Quora is a place to gain and share knowledge. It's a platform to ask questions and connect with people who contribute unique insights and quality answers.
wikiHow - wikiHow is a wiki based collaboration to build the world’s largest, highest quality how to manual.