Ironically, I don't think Stackoverflow does this very well.<p>It's a good article, and the point of researching every wheel ever is a good point well made.<p>But as a long-time Stackoverflow user, I've been frustrated time and time again by cases where extremely valuable content <i>emerges</i> on StackOverflow, but then the moderators come along and kill it because "it is not the defined purpose of this site."<p>Now they have the right to define the rules & purpose for their own site. It wouldn't bother me so much if the content they were killing wasn't so <i>fantastic</i>. But I have seen so many deep, excellent, rich blobs of technical content get cut out and cast aside, for the sake of adherence to some superficial guideline.<p>It seems to be exactly the <i>opposite</i> of "seeing what your users are doing, then helping them do it."