There are a lot of questions which have (often enough) complex and good answers in comments, which should really be posted as answers.
A good example is here: https://stackoverflow.com/questions/tagged/assembly?sort=unanswered&pageSize=50. Virtually all of the questions in "assembly" listed when using "unanswered" have answers provided via comments.
Now I was reading Swarmed with comments which should be answers and notice this comment:
More than that... in case you ask them to post as answer and they don't do that within a day or so, just post your own answer and mark accepted. Case solved. :) – Sha Wiz Dow Ard
And I'm unsure if this was just a joke or meant seriously.
On the one hand, SO should provide answers, and it would be helpful, if the answer is provided in comments, if it were summarized in a real answer. On the other hand, I would feel a bit like a rip off (is this the proper term?) if I would do this from somebody else's comments and possibly even get the rep for it.