Do you ever have that moment? My sister and I have them all the time. Usually when we are together. One of us tells a joke and we are both laughing. You know the kind of laugh where you can't catch your breath and your sides are hurting so bad that you feel like you just did 500 sit-ups. We look around the room and no one is laughing but the two of us. That's when we ask...why are we the only one's laughing?