Tasks to torment a captive

[LockedDummy]

I did a short-ish (10 hours) confinement scene with a Domme recently where I was confined in a space the size of a two-person tent. She gave me two bags of 15-bean soup and told me that she wouldn't open the cage until all 15 varieties of beans were sorted into individual piles.

It was a long, boring, arduous, mind numbing task. My question for the group is...what are OTHER tasks that can produce the same results. I've heard of people mixing grains of white and brown rice together, then sorting those. I know all about writing punishments as well as the various typing-task programs that exist.

I've thought about using crafts that require repetitive steps like cross stitching, or 5d drill projects, or doing a huge paint-by-number with a tiny brush. These are things people might do for fun. I'm not one of those people so it does qualify as a chore. Albeit only mildly sadistic.

I've also thought about taking simple/easy tasks and making them more complicated. Sorting loose change is pretty easy. But with a blindfold, maybe not so much? I have some bondage-mittens that would render my fingers useless. That could make it difficult to assemble legos or do a jigsaw puzzle.

I'm looking for more ideas for tasks that can be used to torture a prisoner. Basically the criteria are:

1) It has to be difficult/boring/arduous etc.
2) It has to be verifiable. the captor has to be able to verify the task was done.
3) It has to be cruel. Presumably, completing the task will result in a reward that the prisoner really wants. So he should have to suffer for it. But it can't be so cruel that it's preferable for the prisoner to simply go without the reward.
4) No complex engineering, programming, or construction please.

All thoughts welcome

[TicleMeEndless]

May be series of puzzles? Something like Rubik's cube for blind. Locked cage, you're hogtied, blinefolded and gaged. You must find and solve all puzzles into cage (you don't know exactly quantity). When you done, press a button on cage's wall. Then Mistress check your work. Every not solved or wrong solved puzzle means another agony punishment. Something real scary, what you know and don't want. "Hah, just solving puzzles" - says you. Try it with nipple clamps and drinked a lot of water before. Add other distractions, like inflantable buttplug or vibrator, and you will take a hard scenario. Call a Mistress or try to find another puzzle? That is the question!

[Brasissy]

how about blindfolded cleaning of your bathroom and or kitchen and you cant remove your blindfold to see until your mistress checks your work.