I love the idea of doing it outdoors but I'm quite shy so I wouldn't make it a hobby for fear of getting caught-I know that's half the fun but I dunno what I'd do if I was!
I've had sex in a park near my house, it was late at night and pitch black and halfway through a bright light shone on us from a building on the other side of the park. We had no idea what it was, if it was directed us or if anyone could see so we just dismissed it lol.
Also had sex in a car, that was pretty awkward, and the changing rooms at my local swimming pool. That was pretty good because people couldn't see us but it was still a public area.
When I was in London with my bf i was in the shower and invited him in to soap me up lol that was very fun, if rather cramped. It was so hot because it was spontaneous, he wasn't expecting it, and the water kinda made me feel like I was in a porno lol