Someone in Florida traded a 1985 TVR 280i Convertible, listed at 18mpg for a 2009 Mini Cooper S, giving them an additional eleven miles-per-gallon toward the goals of the program.

(image via) |
While in Missouri, someone traded a 1997 Aston Martin DB7 Volante (15mpg) for a 2009 Chevrolet HHS (FWD, 25mpg).

(image via) |
Other individual cars traded for which no online, freely-republishable images can be found: a funeral-grade, 1995 Lincoln Eaton from Federal Coach (stretch?, 17mpg); a 1991 Wallace Environmental Wetl 560 SEL (13mpg), a Duntov GT from CCC Engineering (15mpg) and an unlisted 1988 from Aurora Cars Ltd.
All told, the five clunkers which listed mileage in the federal report went from a total of 78mpg to all the way up to 128 after trade-in, giving an additional 50mpg to the environment.