[Overpaid Slacker]

Cars only (no F-Series, VW buses or Land Rovers, etc...)

911/930
BMW 2002
Mercedes Gullwing
Mini/Mini Cooper
Lunar Rover (j/k ... Corvette has to be here, even though I'm not a fan. Can't prop the Mustang, though)
Ferrari 288 GTO
Shelby Cobra
GT40
Alpine A110
Ur-Quattro (though these are neither cheap nor simple to maintain, Seahawk!)

The A110 and Quattro re-defined their sports, requiring either rule-changes or outright mission-specific vehicles to beat them. I would've put the Lancia Stratos instead of the A110, but it was built specifically to beat the A110.

The Ferrari GTO is the car that got me into cars... so it's entirely subjective .. if I was 12 now, the F50 or FXX would probably be the hook. Love the Miura, but it's #11.

I'd probably come up with arguments for/against another dozen cars if I took the time, but these are what occurred to me ad lib...

EDIT -- I wrestled with adding the Beetle, but I just couldn't. It's a commodity, not a vehicle, IMHO. I like 'em, don't get me wrong, but while they score points for being a "peoples' grocery getter" they didn't do much for advancing automobile science or competition. I'd put the VW bus (and its isomers) on the list before the Beetle. JMHO & asbestos suit on.

JP