Honda's W.O.W. concept car has built-in dog crates, washable roll-out flooring, and wide sliding doors. The article notes that in Japan, demand is growing for cars that cater to dogs and their people.
I noticed during my first visit (I'm going to get to go back in a few weeks) that Japan seemed a dog-friendly country, it seemed more common for people to have their dogs out with them in Kobe than in Baltimore. Also more older dogs, it seems they rarely put dogs down just because they get old.