If you could drive at the speed of light...
- Whenever you approach a red traffic light, the doppler shift makes it always look green.
- You can make use of the "slingshot effect" on the curves.
- You can't see a police car's red light in your mirror.
- You can't see reflectors in the road.
- Flashing your high beams at the car in front does no good (actually, your headlights would be useless).
- You tend to miss a lot of the nice scenery.
- Your cell phone wouldn't be of much use unless you were calling people closer to your destination.