KARMA (social network) - Social Media For Good
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.
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.
Blurtit - Blurtit is a Q&A website. You can ask a question or answer on any question.