[throwketchup]

That or you can just listen for tire noise. Even electic cars are quite loud above 25 mph, or so, so it only really becomes a problem at stop lights. Even then, the distinctive power supply whine will let youn that a hybrid or electric is behind you.

[lloeki]

Agreed about tire noise and whine, but the problem is level of ambient noise, and habit. If you have an IC car nearby, even idling, the electric one will be virtually silent.