I saw this suggested in a reddit thread a while back, might've been the Bill Gates AMA, but the comment was something to the effect of, "What if cancer researchers could post things they've tried in some central location, without the overhead of publishing papers in a journal?"
This wouldn't have to only apply to researchers. I had a similar idea while ago for a site where motorcyclists could post how they got into an accident so that others could avoid the same fate, like an informal NTSB-style accident report.