The big fiberglass mascots on the side of the road in my childhood? They were called "muffler men". Drjim of Every Blade Of Grass has turned up fascinating links on this piece of kitschy Americana. For some reason I found them scary when I was little, and I wasn't the slightest bit surprised when one got all animated and tried to attack somebody in Stephen King's It.
Maybe that's why they're kinda nostalgic for me now: They represent the dangers of a simpler time, and it would be nice to go back to the days when my worries were leering fiberglass mascots and the Hamburglar instead of Congress and the federal bureaucracy. For one thing, unlike Congressmen, there's no law against shooting fiberglass mascots, so long as they're your fiberglass mascots and you do it outside of city limits.