I can out-smug you - my car has no exhaust pipe and is virtually silent!

(Nissan LEAF, and yesterday I was pleased to find myself behind another one in my home town traffic)

Relevant to original post too: buses (school or otherwise) are an ideal candidate for electric power, considering they spend much time standing still with the engine running polluting the air that the children breathe, and they don't have to go very far or very fast.