I like the idea of a folder for obsessions and a folder for perception, cognition, and sensory issues. As Civet indicates, these are broad topics that will apply to a large number of people. I strongly support the addition of broad topic folders, as the general folder has been hosting a very large number of posts recently. It's difficult to justify creating folders for narrower areas, though, as this would make the structure of the forums much more unwieldy.
Since we're brainstorming, what do you all think about a folder for health issues that would include medications/treatment, diagnostics, sleep-related issues, and general health discussion? I think this would be a very broad topic, as well. Perhaps hale_bopp's idea of a supernatural folder could be expanded to include philosophy, religion, spirituality, supernatural beliefs, and mythology. I think that would be sufficiently broad to merit a folder.