I just posted some larger photos of USAF X-51A Waverider Hypersonic Test Vehicle that will be tested next week. Powered by a Pratt & Whitney Rocketdyne SJY61 scramjet engine, it is designed to ride on its own shockwave and accelerate to about Mach 6.
Link to gallery:
X-Planes (USAF) - Military Pictures - Air Force Army Navy Missiles Defense
Link to gallery:
X-Planes (USAF) - Military Pictures - Air Force Army Navy Missiles Defense