The front lawn.
On the hood of the car.
In the pool of a local hotel, late at night.
On the beach, during the day.
In the boss' office at work. (and no, not with the boss, thank you)
When I was younger, at my parents house, in my bedroom, with my parents home, with the door open, and they had no idea..
One of the funnier ones I've heard about: I used to work with a girl who worked at Disneyland, and she said that the Matterhorn has an elevator that goes up to a little room in the top of the mountain, and that people are always going up there for that purpose.
-j