Ummm, duh -- ever heard of the Corvette? It's too heavy for my taste, but it cleans up in many comparisons, particularly those considering price.
Corvairs -- especially John Fitch versions -- were a blast. I owned three, during my mostly Alfa period.
The Grand Am was not even close to a sports car, but the Fiero was. Unfortunately, by the time Pontiac got it right -- the 1988 Fiero GT -- they had already killed it in the market.
And then there's the current WCM Ultralite, which is simply terrific (think Caterham with the S2000 drivetrain...)
-- Larry