For me it's music. I commute about an hour each way and would go crazy if it weren't for my CD's. I also make a number of trips each year to visit relatives in Upstate New York and I find that properly planning the music the time flies by.

I enjoy reading and find it very relaxing and usually do my reading in bed. I very rarely get the time to listen to music when not in my car. And my musical tastes aren't shared by a lot of people, so my car is my musical sanctuary.