In the book (and movie) Dune, The Bene Gesserit Reverend Mother Gaius Helen Mohaim tests the young Paul Atreides with a box that induces pain.
Paul puts in his hand and the Reverent Mother holds a poison needle to his neck. She tells him that if he removes his hand, she’ll stab him with the needle. The box induces excruciating pain in Paul’s hand, but doesn’t do any damage.
There’s no way you wouldn’t want one of those, right?
So I made one. It wasn’t my idea, I got it from an article linked to by – I think – Boing Boing. The article explained that if you line up cylindrical objects which are alternately pleasantly warm and pleasantly cool then put your hand on it, you’ll experience excruciating pain.
And it works!
For some reason, your nervous system is fooled into sending you a pain signal. Even with a low temperature differential (warmish and coolish bars) the pain was barely tolerable. My proof of concept used an especially high-tech approach: hotdogs. I put half of them in the freezer for a few minutes and warmed the others. Then I just laid them on the kitchen worktop, hot cold, hot cold.
The proof of concept was so successful that I’m thinking of making an electric version in a proper box. I don’t know why, it just seems like a cool thing to do.
Then you’ll have even less reason to come to my house.
As a bonus, Fortran enjoyed eating hotdog afterwards nearly as much as I enjoyed making a pain machine.