Three Apple engineers and three Microsoft employees are traveling by 
 train to a conference. At the station, the three Microsoft employees 
 each buy tickets and watch as the three Apple engineers buy only a 
 single ticket. 
 
 "How are three people going to travel on only one ticket?" asks a  
 Microsoft employee. "Watch and you'll see," answers the Apple engineer. 
 
 They all board the train. The Microsoft employees take their respective 
 seats, but all three Apple engineers cram into a restroom and close the  
 door behind them. 
 
 Shortly after the train has departed, the conductor comes around 
 collecting tickets. He knocks on the restroom door and says, "Ticket, 
 please." 
 
 The door opens just a crack and a single arm emerges with a ticket in  
 hand.  The conductor takes it and moves on. The Microsoft employees saw 
 this and agreed it was quite a clever idea. So after the conference, the 
 Microsoft employees decide to copy the Apple engineers (as they always do)
 on the return trip and save some money (being clever with money, and all 
 that). 
 
 When they get to the station, they buy a single ticket for the return  
 trip.   To their astonishment, the Apple engineers don't buy a ticket at 
 all. 
 
 "How are you going to travel without a ticket?" asks one perplexed  
 Microsoft  employee. "Watch and you'll see," answers an Apple engineer. 
 When they board  the train the three Microsoft employees cram into a 
 restroom and the three Apple engineers cram into another one nearby. 
 
 The train departs. Shortly afterward, one of the Apple engineers leaves  
 his  restroom and walks over to the restroom where the Microsoft 
 employees are hiding. He knocks on the door and says, "Ticket, please..."