Four guys who work in Boston form a carpool. Unfortunately, the route takes them through the "Big Dig" tunnel, and one of the fellows is very fearful that the roof will collapse and the tunnel will flood. Unfortunately, there is no good alternative route that avoids the Big Dig. He goes to his doctor to see if anything can be done about this anxiety. The Doctor tells him: "We're seeing a lot of this in Boston these days. You are suffering from 'carpool tunnel syndrome'."