Most Unusual Cause of an Orgasm?

A few times I've been walking and had a flash thought of something sexy my partner (it's happened with multiple partners) was doing to me, and I started to orgasm. Almost always near stairs, too. -_-

Saw an erotic drawing. It didn't even show any real nudity. Had an orgasm about 5 seconds later while staring at it.

Oooh, art. Do you know the title of it, or was it a more private drawing?

Riding in a vehicle where there was a lot of vibration in the seat.

Hmm... I'm not sure I've ever orgasmed unexpectedly like this before.

I'd been on a boat (shared sleeping cabin with family so no masturbation) for a week. We made it back to the harbor, and after turning off all the lights and instruments, and pumping the bilge, it was finally time to turn the engine off.

Stepping into the hot engine room, the door shut behind me, everything on the boat was off except the monstrous diesel engine. Pitch black, the engine room full of mechanical heat and the smell of lubricating oil, I spent almost a minute breathing it in. I reached for the kill switch (a throttle interruptor dial) and when I touched it, the vibration of the engine shot through my fingers and straight to my crotch. I had one of the strongest, wettest orgasms I can remember.

Finally shut the engine off, and had to acknowledge to myself that I'm a fetishist. No denying it after that! Luckily I could pretend my weak knees were the effect of sea legs.

One time during the summer me and my husband had just stopped after a hot sex session where I had squirted multiple times and I was sweaty, and I moved towards the fan, and soon as the air from the fan hit my clit, another orgasm and it was incredible!