Has anyone driven a long way with a crawler?

Were in the military so we travel alot for holidays and move alot, since my baby started crawling we havent traveled. When he was younger he did great in the car for the 12 hours we drive, but now since he is crawling he hates being restricted for a long time, not even for 45 minutes in the car. What are some ideas you have to keep my roamer occupied and happy in the car for 12 hours? Thanks everyone.