Risky game of chance, typically played by the lower classes or students, where a much-needed visit to the toilet is followed by the depressing realisation that there is a very limited amount of toilet paper at the user´s disposal.
Guy 1: "Last night, Mandy invited me round for a free manicure as part of her beautician´s course."

Guy 2: "Wow, she is so hot. How did it go?"

Guy 1: "Pretty well until it became abundantly clear that I play the Fingernail Lottery every week."

"Such was my urgent need, I locked the toilet door in great haste, lowered my britches and dropped some friends off at the pool. Only then did I note the dire lack of toilet tissue. My heart sank in the sad knowledge that I would have to play the Fingernail Lottery."
Hard Times, Charles Dickens
by Francois Fromage June 8, 2010
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