Ive been thinking about this for a while. I know my Master will eventually come up with it (i think hes touched on it before) but the different things you can do with corner time is pretty interesting.
"Hold this quarter to the wall with your nose. If you falter or pull back in the slightest, the coin will fall, and your time will be doubled."
Or something like that. And the person has to keep doing it until they complete the time. It could even exceed into something where they've dropped it a bit and they have built up some time, it could be like,
"Oh this is just fantastic.You've aggravated me and waisted so much of my precious time, you've driven me to hunger. I'm going out for food. Your punishment is to stay like that until get back, regardless of time. If your lucky and I happen to be feeling particularly merciful, i might bring back some of my leftovers for you."
hee hee. or if hes feeling really really nasty, he sits on the couch, eats snacks, watches TV, and once and a while shoots rubber bands at the slave, making them squeak and drop the coin. XD