You know that feeling when you have to go so bad, you can hardly see straight? All of your senses auto-tune into a radar for any sign of a restroom.
I don't think there is any way to accurately describe that feeling of pure joy and relief when you finally get to go.
Hey, maybe this is TMI, but you all know what I'm talking about. And I drink over a gallon of liquid a day, this crosses my mind a time or two.