If I really want to point out one single bike from history that I love. That would really have to be the Honda NSR500. It was much before the era of 1000cc Moto-GP bikes, these two strokes machines ruled the roost.
I thought this thread would generate some conversation.
To make a more thoughtful response than above, the sport bike that actually tempts me would be a BMW boxer. I like the R Nine T Pure, and even and older, like 1970s older, boxer from back in the day would have character. I would consider them to be sport bikes, but not supersports.
I also like some of the hipster bikes, such as the Bonneville Twin and Kawi's Z900RS. But I like them because they remind me of the bikes that were around my neighborhood when I was a kid, rather than creating a nostalgia for something I'd never seen before.