Controllers with turbo buttons have existed for many years, going all the way back to the NES, and controller mods for the 360 are nothing new. But having a turbo button (among many other things) modded into what looks like a standard controller is news to us. The guys over at HGcontrollers seem to have started up a fine little business doing just that. The above graphic is really from their site (can you spot which are the real and fake buttons) and details some of the special enhancements made to the controller for the express purpose of playing shooters.
The goal of these mods is to create a controller configuration that can be played through the entire game experience without having to remove one's thumbs from the sticks. Theoretically, this means that your aim with said sticks will improve, as you no longer have to take your thumb off it to hit the essential buttons. However HGcontrollers does more modding of controllers than simply moving buttons. The staff there will actually create a controller with a custom button layout, toggle switches, microprocessors (turbo) for rapid fire, and more if you've got the cash for it. In fact, their website seems to be a bit behind the times forgetting to tell its readers that there are even controllers specially built for Gears that do your Active-Reloading for you. These controllers look great and all, but specifically modding (or buying) your controller to get better at a game sort of defeats the purpose (FUN!) for us here.