Foreplay while out and about

With the obvious difficulties of having sex in a car, I expect many people have fooled around just shy of the full deed. Could be in a car, train, or plane. Might have just been some sneaky hands in a restaurant booth or on a park bench. Flirting and discreet physical teasing is an art form on its own.

What sort of dirty fun have you and another gotten into while out and about? Did it get you all worked up and ready for hot sex to happen later?