A blonde left her car out in a hail storm. When the storm was over she
checked the car and found out it was covered with small dents. She went
to the local garage and inquired how to fix the problem. The mechanic
jokingly told her to blow on the tailpipe and the dents would be
removed.

So, she took the car home parked it and proceeded to blow on the pipe.
Another blonde came by and inquired what she was doing, she told her she
was blowing on the tailpipe to remove the dents. The other blonde
responded, "That's not going to work unless you roll up the windows!"