My vote would have to go to either the Pontiac Aztec, the Fiat Multipla (picture attached) or many of the Citroen design abortions that they have foisted upon the world, loe these many years.
Word has it that a Citroen design team, that just could not consistanly produce an ugly enough car design, was fired, and then hired by Fiat. Their first effort at Fiat produced the Multipla. This picture of the Multipla just does not convey the horror and instant wretch reflex that your visual cortex transmits to your unsuspecting gut.
You will notice the puke green color of the transportation device, dare I ever call it a car.
