There's a double overpass close to where I live and for some reason the acoustics generated when you drive under that overpass are phenomenal. I always have to "goose" the throttle just a little bit when I drive under it. Couple of my buddies came to visit me a while back and I let them drive my Z. Had each of them drive under the overpass and give it a bit of throttle. They too thought it sounded pretty awesome.
This video does it no justice however... (skip to 3:05 minute mark)