Daniel of NeuroInterests posted an interesting story. Functional MRi studies have found many parts of the body to be orgasmic. The scientists think that excitation of the hand, mouth, etc. activate the same systems as a genital orgasm. If that's the case, it means these anywhere-orgasms also release oxytocin.
When I was very young and inexperienced, I had a boyfriend who used to stroke my hand during class recess. I'd spend the entire class squirming in my seat. I had no idea what was going on. Wish Iwas that sensitive today.
Here's the full NeuroInterests post, with a link back to the original story.