The next generation of cars is actually already in development. As is the next generation of highway. The autonomous car will make drunk driving a thing of the past. It will curtail accidents and quite possibly even make street lights obsolete.
There is a system in development that uses a linked guidance system between autonomous cars and public transportation. What you can is drive behind a bus that has the system, activate the linked guidance network, and your car follow it at a safe distance. You can resume manual operation at any time.
Both the autonomous and the linked guidance systems are currently being designed. It will be interesting to see which gets to market first. Mercedes already has an advanced guidance system for their cruise control that let's the car steer automatically using the stripes on the highway as a guide. It's pretty useless on roads where there are no stripes but it's a pretty good start.
The flying car? We might have it when we have apartments on the moon. The propulsion system and take off requirements makes them just too dangerous and impractical for consumer use. There have been several "flying cars" already brought to market, but they are classified as a sports plane and you will need a sports pilot's license which is easier to get than a pilot's license. But even though you can drive it as a car, I would never do it.
Amphibian cars? We've had them for years, they just look to embarrassingly dorky to drive around. Although I have never seen a Jet Ski motorcycle, that would be cool.
Hybrid vehicles will always be impractical until someone devices a propulsion mechanisms that functions equally efficient in both in environments. For air and that would probably be anti-gravity, which means that you could also probably use it in water in conjunction with jet propulsion. And anti-gravity won't be happening any time soon.