for MOST UNUSUAL places - I can think of two. Both of these are from when I was still young (under 12).

The first was an old transit bus that was parked beside the river and being "re-purposed" as a duck blind.

The second was an old abandoned house in the woods that was on the verge of collapse. In fact, the ground floor had already caved in and I had to tiptoe around the edge to get to the stairs and up to to the second level where I kept some "liberated" outfits from my grandparents' attic.