a) the lady on the tills has to be reminded to give you back your debit card after paying for your groceries.
b) you discover that the mild disagreement you had with your boss yesterday concerning exactly which week off week you have got coming up, might actually be based on correct information on his part and not yours.
If you'll excuse me, I have to go knock a few heads together in the Duties room at work.
UPDATE: The lovely uk_lemming has cheered me right up with this tale of the smartest hacker in the world.
But then I think foenix trumped it with the alf-f4 story.