Was in college in Florida and found an old plate beside the railroad track. Picked it up and was walking back to campus when a cop car screamed up, the cop placed me under arrest and made me get into his car (don't remember if I was in handcuffs at that point). He ran the number and said, "If it comes back, you're going to jail!" Well, I was sweating (and not from the Florida humidity) but the plate came back as not-reported-stolen. So I was allowed to go on my way. But, you know what? I stopped picking up license plates after that.