I have one giant folder, where I have most of them located, though I saved the preview pages to replace the folder icon, so I can easily see what I have, colors, etc. I do have my Christmas kits in one folder, so I can see them all at a glance, and I have my layered templates in another (same reason). I've realized that the more I tried to categorize them, the less I could actually see them, and so I would forget I had it.