I've also done it in a car while driving, in my van while sitting in a drive through (covered up), into the urinal at work, sitting at my bosses desk after hours, standing right in the middle of the kitchen floor, with my parents in the next room, while my Mom's friend watched me. I masturbated a girl, while standing in a roller rink, by the concession stand, & in a stairwell at school.
I admit it, I'm a perv. Never where I could be seen by kids though.
ive masterbated while driving, public shower, public hot tub, in a tree, standing outside at night, pretty much the same places ive had sex, exept the tree, now that would be damgerous. a friend of mine that was in the navy used to rub 'em out while sitting in the torpedeo room.