There's no denying that Kasparov is hardcore. Observing Fischer's win over Spassky in 92, he reported, "Bobby is playing OK, nothing more. Maybe his strength is 2600 or 2650. It wouldn't be close between us." By no means the ideal candidate to outchess our mechanized would-be masters.
My favorite Fischer is, of course, deranged bum Bobby with ragged beard and passport accessory.