Go to Target and look at what are called document safes. They come in different sizes, but the point is to have one you can lock.
So, obviously, someone could pick these safes up and walk out with them, but that's not the point. What you want is a place for the important stuff, so you can keep it in a special place and know where it is: passport, blank checks, receipts, etc. Stuff you don't want laying around for just anyone to see. Maybe those notes from your first girlfriend in 5th grade. Whatever.
