After all these years, I struggle to think of any car that has more raw exotic appeal as the Lamborghini Diablo. I think, personally, it's the most exotic car ever made and probably ever will be made. Pagani gets close, but even the earliest versions of those cars are pretty space age by comparison. The Diablo is hand made and wild. The proportions of the Diablo are extreme even by today's standards, and the rear end is just so sexy, on any of the models. I'm spoiled to supercar sightings where I live, but on the rare occasion I spot a Diablo it still feels like a proper event.
Something about the science & engineering of the exposed mechanicals, counterpointed by the flowing curves in the fenders and lighting, is absolute perfection in my eyes.