Personally we would just turn on the air conditioning in our car but this is definitely an interesting alternative way to beat the heat.
We have to admit, we were as baffled as the local police officer in a small German town who discovered one BMW owner that had actually made his BMW E36 into a driving jacuzzi. The Associated Press reported that the officer on site spotted the four men in the water while their makeshift E36 hot tub traveled down the road. Three of the four men fled the scene. The fourth was apprehended for driving without proper registration as well as for possible, and very likely, driving while under the influence.