I lost a $300 switchblade that I accidentally had on me when I was about to go through security for my sister's college graduation. Had an "oh fuck" moment while standing in line, and then in what was retrospectively a very conspicuous moment of panic I stepped out of line and went around the corner to toss it in the bushes. Pretty sure one of the security guys went and grabbed it like a minute later because it was gone when I came back.