My favorite...
Go grocery shopping and try carrying 5-10 heavy, grocery-filled, plastic bags in each hand, while using your fingers as your only support.
Individually load each finger with 1-2 bags and once all fingers are full, form a tight fist and go up a few flights of stairs with those bags and then after unloading, try masturbating with those numb fingers.
Result: You will feel as if a stranger was pleasuring you.
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