On Wed, 21 Dec 2011 11:48:39 +0000, Martin Brown
wrote:

The alarming thing about Prius at low speeds in carparks is you don't
hear them starting up the engine at all before they move which can be a
bit disconcerting as a pedestrian. They are too quiet when moving off!

Easily solved by having a cheery tune from a PA speaker under the
front bumper.
If it's Drivel's I'd suggest the Dance of the Sugar Plum Fairy.