well i don't need them anymore, now that i'm old enough to not care.
but when i was younger, i used to hide pellet guns, knives, booze and files in my ceiling.
now, the booze is in the open, chilling (not chillin') in front of my air conditioner, coz the temperature's been in the 100s this whole week.
the pellet guns are mostly sold off, and the knives are just in a drawer.
the files, for the most part are digitized and kept all over separate hard drives, internal external, and flash.
EDIT: also, if you're too lazy to actually hide folders with admin tricks or lock programs, you can do what i did as a kid, just get a folder, name it comma (,) or something small, and take the folder picture away. then get a really complicated desktop picture and hide the punctuation somewhere in it. surprisingly, it works really well.