Sound deadener?

[vette427-sbc]

Anyone have any recommendations on a good sound deadener? Im not worried as much with the heat insulating characteristics as I am the sound.
I like Dynamat, but its way too heavy to do the entire interior in and their lightweight product is a little pricey... lizard skin sound insulation looks like a contender. Any other brands? Bed liner?
Weight and cost are the biggest concerns here...