Blonde: "I'm on the road a lot, and my clients are complaining that they can never reach me."
Psychiatrist: "Don't you have a cell phone?"
Blonde: "They're too expensive, so I did the next best thing: I put a mailbox in my car."
Psychiatrist: "And do you receive any letters?"
Blonde: "No, but I figure it's because when I'm driving around, my zip code keeps changing."