This week on Car Talk, Howard needs to drive a mattress from Boston to "Hunga-Dunga" and wants to know how to get negative lift, and keep it from flying off the roof of his car. Tom and Ray know one method that won't work, as evidenced by an ill-fated attempt to transport 18 sheets of plywood. Elsewhere, Peggy swears she heard the guys recommend mixing kerosene and water to wash a car, but isn't calling to sue for damages. Also, Scott's concerned about his truck not starting, but more worried about his friend "Fat Tony" fiddling around with his big bucket o'tools; John managed to lock himself out of his car with the engine running and chose the most painful way to shut it off; and if Tom and Ray help Gillian translate a French truck description, are they really doing work for the CIA? All this and more, this week on The Best of Car Talk.