I had this happen a couple of years ago at work in our corporate office building. It was a Wells Fargo ATM. I'm walking by late in the day and the machine is beeping like crazy. I walk over thinking someone left their card in there so I was going to grab it and turn it in to security. Instead of an ATM card, there was $200 in cash. I took the $200 and went to the security desk and turned it in, didn't think twice about it as I would certainly want someone to do that for me. They were shocked. They said they get stuff turned in all the time (even money once in awhile), but never that much. They had me fill out their standard form they have people fill out when they turn something in and said if no one claimed it in 30 days, they would contact me and it was mine. I thought, "Ok, but what are the odds of no one asking about their missing $200 in a secure corporate office building?" Sure enough though, 30 days later I get the call, no one had claimed it and they gave it back to me.