After viewing all these last night I came up with a new one. Enjoy
Hahaha!
I left a rubber mallet on my roof, about half way home from work I heard a clunk and remembered I put it up there... Got home and it was wedged in the spare tire carrier. HahaI once left a flashlight between my stock bumper and grill on the thing that covers the frame rails. I drove around all day running errands and noticed it was still there that night.