There's something to be said about old pump guns and I mean OLD. Specifically, the Win M97, Win M12 and Ithaca M37.
Fan fired. That is, you depress the trigger once and while keeping it depressed, mere pumping of the action will cause the firearm to discharge. Depending on your dexterity, it's possible to empty the magazine in a matter of seconds. Fast? Yes. Loud? You betcha.
New is nice, but don't discount the old. Anybody, did I miss any other old guns?