Two men walk into a bar (both miraculously avoiding the quick and easy punchline). One of them orders a pint of bitter and the other orders just a slice of lemon. The one with the bitter gulps it down while the one with the lemon has a suck on it and gives up. On the next round, each orders the same - a bitter and a lemon. Before the third round, the one with the lemon says to the other: "Do you fancy a wager?" and the other replies: "Yes, but is it about the lemon?"