The first car I ever wanted was #6, the amphibious truck. I still want one. While everyone else wanted a pickup, I had one of these in mind. For somewhat less amphibious driving, I've got a soft spot in my heart for the Unimog, converted to a camper. I think you can still drive through six feet of water, but it doesn't float.
True story: When I was a kid, I lived within easy walking distance of a patch of unused land that was a dump for WW2 trucks, armored vehicles and other equipment. It was overgrown with vegetation and you couldn't see it from the road. We used to spend a lot of time playing in there, crawling through the half tracks and troop carriers and specialized vehicles. Heaven for a 10 year old boy!