We recently reported on some pretty powerful Hummers coming from Predator Motorsports in San Marcos, CA. Well, it turns out that tuning Hummers for performance is a growing niche market, as GeigerCars.de out of Europe has surfaced with what it claims is the world's fastest Hummer. The German tuning company takes the standard 6.0L V8 in the Hummer H2, bores it out to 7.0L, adds an intercooled supercharger and other engine mods to create a monster motor that produces 700 horsepower and 666 lb-ft of torque. The Hummer needs all that power to rotate the gigantic 28-inch rims it's wearing and achieve 62 mph in 6.5 seconds. The package also includes suspension, brake, interior and exterior mods that fill out the immodest $238,680 asking price.