Is there a place where useful information can be posted without actually asking a question? For example, while doing some research, just prior to asking a question on SuperUser, I found the answer. It isn't something very obvious or intuitive though, and it'd be nice to post it somewhere, so others (or myself) can find it in the future. I've seen the check-boxes for the "community wiki," but I've never seen it. What/Where is it?
Ask the question as if you hadn't found the answer, then answer the question yourself. This behaviour is in fact encouraged.
If you are lucky you may even get an answer that is better than the one you found. But if this does not happen you can accept your own answer after 48 hours.
You should NOT make it a wiki, if the question and the answer are good you deserve the up votes.