Depending on your definition of "justified" and "justifiable", you may run into the problem that eventually your beliefs depend on other believes that depend on other beliefs, and so on until you reach an axiom. And this axiom may be "unjustifiable" or "unjustified", but you "need" to believe it in order to have any beliefs at all.
One such axiom may be that your brain is "sane", in the sense that when it tries to use logic to reason about something, you can trust the conclusion. For example, let's say your thoughts are "All A are B. C is an A. Therefore C is a B." Can you trust the conclusion that C is a B? Well, maybe you might revisit your thoughts, starting from the first statement "All A are B". But wait, was that really the first statement? Here you're relying on your memory, that you can correctly remember what you were thinking about just 2 seconds ago. Is that belief justified? How could you know?
What do you believe that most people on this site don't?
I'm especially looking for things that you wouldn't even mention if someone wasn't explicitly asking for them. Stuff you're not even comfortable writing under your own name. Making a one-shot account here is very easy, go ahead and do that if you don't want to tarnish your image.
I think a big problem with a "community" dedicated to being less wrong is that it will make people more concerned about APPEARING less wrong. The biggest part of my intellectual journey so far has been the acquisition of new and startling knowledge, and that knowledge doesn't seem likely to turn up here in the conditions that currently exist.
So please, tell me the crazy things you're otherwise afraid to say. I want to know them, because they might be true.