Secret services

Yep. My mother and I were traveling across the country on Greyhound (a bus line). At one stop, a man got on who was behaving in a somewhat peculiar manner. It *was* winter, but he was very bulked up in his clothing. He carried with him only a single, small bag, and he wore sunglasses - despite the fact that the bus windows are tinted. He even wore them to sleep in. We were on the same route for well over 10 hours, and heard him speak once, with a very thick non-American accent. At one stop, we were going to have a 15 minute hold. My mother and all of the other passengers got off of the bus - except that strange man. A few minutes later, men in a variety of clothing - mostly army fatigues and business suits and government/police shields were talking to people outside of the bus, and then they boarded the bus, checking every seat. After about 5 minutes they left. At the next stop, the man left the bus and changed his travel plans to the opposite direction that his original ticket had been for. Things that make you go HMMMMMMMMM

Nope, I've never had a run-in with secret services, although I've always imagined it to be kind of cool if I do. However, the reality of it would probably reduce me to a trembling wreck sweating in fear