I don't know much about the temple cars, or chariots, which you see in nearly every temple of any size. The idea is so important that it is even incorporated into permanent non-movable buildings, like the rather weak one on the lower right. These are the juggernauts that devotees have been known to throw themselves in front of, in a holy suicide. One of the great temples of India is built in the form of a huge stone juggernaut, and the image of its great stone wheel sits in the centre of India's flag. The golden car of Thiruvanmyur (lower left) is the most extravagant that I have seen but far from the largest, which can be three stories high or more. I think the little shrines with little idols that I have seen being carried on one person's head are simply small versions of the same idea.