My favorite response she had for that question was "What, again?"
We do get a story every so often, of someone forgetting to put gas in their plane. This doesn't necessarily have to be an unforgiving situation if you keep your wits about you. Most planes don't plunge out of the sky the second their engines stop. Bob Hoover demonstrates this quite effectively. If you're flying a gyrocopter, they can get down on autorotation. An ideal flying car would have one of these characteristics.
If you want a flying car now, go buy a small airplane -- you can get a used Cessna for about what I paid for my car. There are a number of ultralight possibilities, too. You'll still need to be cognizant of the FAA regulations governing your flight if you're in the USA, so you won't really be able to treat it like a flying car. But that's as close as you're likely to get for the next two or three decades.
Einstein, Tesla, Newton, Boole.
Contributions way the freak ahead of their time, and not just the knowledge they knew, but what they decided to do with it, was probably pure genius in my opinion.
There are lots of smart people in the world, but very few of them really contribute anything beyond paper test scores or academic nonsense.
To be a true genius in my opinion, you look the world straight in the eye, tell it your full of crap, and whack upside the head with a contribution that challenges civilization at the time.
All of the above men did that, some centuries before their contributions fully took root.