I'm of the opinion that the hours between midnight and 4 A.M. (see 4AM Syndrome) are the best times to be awake, precisely because no one else is. I just love walking down the middle of the road at night, listening to the sounds of the insects and dogs, as I partake of my nightly Quest To Go Buy Skittles.

It's also cool because you can sit outside and meditate, and there's no one around to disturb you.

And it's also ALSO cool because I live in Sierra Vista, Arizona, and those hours are cool enough to go outside even during the hot summers.

The world is almost surreal at those times, and the atmosphere is very empowering. A group of 5 or 6 friends walking around at this time is even more so. (see: LAN party)

Perhaps I'm going a little too far with this, but perhaps this is an argument for decreased population density- big cities don't quite have the same feel, because there's still traffic at those hours.
I think I've finally figured it out. It's because at 2 AM, no one is around, so there's no sound. The sun is gone, so there's no light. All that's left is you and the universe. Your senses tune themselves up to compensate, so the lines in the road seem brighter.