There are only two of the Bugatti Atalantic type 57SC, one at the Mullin Museum (highest price ever paid for a car), one in the Ralph Lauren collection.. but even cars this expensive have been in the classifieds

 above from my post 2 years ago http://justacarguy.blogspot.com/2010/01/some-amazing-things-turned-up-in.html

Bottom image from http://karamelocycles.blogspot.com/2011/06/bugatti-type-57s-atlante-1937.html

3 were made, one was hit by a train in 1950. So one of the above was the car in the calssifieds.

(1 of 206) 1969 Z28, JL8 optioned, stripe delete... was sold in 1977, and finally bought back in 2010... wow! Home after 33 years, with only 22,133 orig miles

 Original everything, paint, interior, hell... it's probably got 1969 air in the tires!

the second owner put it in the garage in 1982... and left it there... BARNFIND!

this is a X-33 car and was ordered with custom (deluxe) interior, fold down back seat, radio delete, headlight washers (only 116 non-RS cars were ordered with this option), and rear window defroster.

Tom sold this car in 1977, located and purchased it back in Feb. 2010.  Not only is it a 22,133 mile 1969 Z28, but it is a rare JL8 Factory Option  (Four Wheel Power Disc Brake 1 of 206) and a Stripe Delete car.  He still has the Warranty Card & Protect-O-Plate that he kept when he sold the car in 1977, not for any reason except they were not important back then and rarely did anyone ask for it when they were purchasing a car from a private party

1922 Bugatti type 23 Brescia

raced in 19 of 23 Indy races, more than any other racecar, and once owned by Charles Bronson, this Harry MIller and Earl Cooper 1927 racer has pedigree and history

1923 Avoin Voisin factory research race car, the C6 Laboratoire, simply a most amazing innovative and obscure try at a racecar from airplane engineers

 Quite odd looking, maybe the strangest I can recall ever seeing

 Why it has a prop on the nose, I'd only guess that it's for airspeed. Boardtrackfan commented that he thinks its for a water pump

 and I was astonished to see it has the actual "Windscreen" that I've only heard of but never seen before

Click on the above gauges and get a good look at the full size... those are pretty unusual

 and a square-ish steering wheel... boardtrackfan reminded me that this isn't so uncommon, it's so the driver has a better view when driving straight, and more legroom

  here is the big indication of the aeroplane style engineering they brought to their race car... cable brakes. But not connected to the brake pedal, this is independant front and back brakes for a racing advantage

1955 Ferrari 750 Monza Scaglietti Spider, one of 35 built, race winning in Phil Hill's masterful hands, and starred with Fred Astaire driving it in a Gregory Peck movie

found on http://driven.urbandaddy.com/2011/06/08/the-fred-astaire-1955-ferrari-750-monza/

1935 Hispano Suiza J12 (drophead coupe / convertible)