Two old guys, River Rat and Derek, were sitting on their usual park bench. One morning Derek had just finished his morning jog and wasn't even short of breath. Rat was amazed at his friend's stamina and asked him what he did to have so much energy.
Derek said, 'Well, I eat rye bread every day. It keeps your energy level high and you'll have great stamina with the ladies.'
So, on the way home, the Rat stops at the bakery. As he was looking around, the lady asked if he needed any help. He said, 'Do you have any rye bread?'
She said, 'Yes, there's a whole shelf of it. Would you like some?'
Rat said, 'I want 5 loaves.'
She said, 'My goodness, 5 loaves... by the time you get to the 5th loaf, it'll be hard.'
Rat replied, 'I can't believe it, everybody in the world knows about this but me.'!