Here's another one my perverted mind came up with in the wee hours one morning. Of course I don't play with my wife (yet) but here's the general idea:
It's called "Don't Cum". She would unlock me and lube up my shaft with lots of coconut oil. She would start a countdown stopwatch, say 10 minutes. I would stroke myself using just my first finger and thumb touch tips from the bottom of the head to the base of the shaft. I wouldn't be allowed to take my closed fingers off of my penis--so my fingers would never come above the head. She has a second pace timer which beeps every 2 seconds. I would have to maintain pace and complete a down and upstroke in that 2 seconds. Occasionally she would call out either 1 or 2, with 1 being the tips of my thumb and first finger touching to 2 being the tip of my thumb touching the first knuckle of my first finger. The 2 causes a very tight grip and would usher in an orgasm if left on very long. I still would have to maintain the pace of stroking to one complete up and down per 2 seconds. She would alternate between a 1 or 2 grip. Maybe if I make it the full 10 minutes the next day we'd have PIV or reward BJ. But if I fail and make myself cum then locked for another indeterminant period of time.
He stays locked up the first week of the year. After 7 days he is unlocked and then KH starts a timer manually stroking him until orgasm. She then stops timer and relocks. This is now the new time to beat--the maximum time spent stimulated the following week. Each week the same process: KH unlocks, strokes until either orgasm or timer expires--which ever comes first. If orgasm occurs before timer then that becomes the new time to beat. Repeat each week with the new record time of either orgasm or time expired, then relocked.