The Navy's new M-80 Stiletto is a prototype for a small specwar littoral combat vessel. The hull is constructed of carbon fiber. It's 27 meters in length and four Caterpillar C32 engines push it through the water well in excess of 50 knots.
I could buy one for $6 million, however insuring it, fueling it and maintaining it would be a continuing blooding - but it sure is cool!
Definition of boat: A hole in the water you pour money into.