I've always found the reading-in-the-car/motionsickness thing to be very interesting...

I was affected by it for a long time, then suddenly I decided to simply try to 'will' myself out of it, psyching myself into believing that it was all in my head anyway.

The surprising thing is I believe it's worked for me. Telling myself I won't get sick allows me to get caught up on books during long car rides. If I think I will, I'll be horribly nauseous.