To answer your question, it is legal if you do it right. There is a Meta.stackoverflow question that goes into some of the details, and gives a list of sites that do such:

https://meta.stackexchange.com/questions/24611/is-it-legal-to-copy-stack-overflow-questions-and-answers

That's an edge-case, though likely infringing. I'll poke some of the SE people who check into these things.

Edit: Looks like a bad site. [Reported][1].


  [1]: https://meta.stackexchange.com/a/121253/131633