It ended up in a hangar covered in bird crap, that's what. A remnant of an unhappy time in NASA's recent history, the Orbital Sciences-built X-34 was photographed by Ashley Wallace in storage at Edwards AFB in California. The X-34 was built as a flying testbed to demonstrate technology for future low-cost reusable launch vehicles.
(Picture by Ashley Wallace, from airliners.net)
The unmanned X-34 was intended to be air launched from Orbital's Lockheed L-1011 mothership and accelerated to Mach 8 by a NASA-built oxygen/kerosene rocket engine. The vehicle was designed to land on a runway and fly up to 25 times to test composite structures, resuable propellant tanks and thermal protection systems, and autonomous flight operations.
Orbital got as far as captive-carry tests on the L-1011 before the X-34 was cancelled in 2001, along with Lockheed Martin's mightily ambitious X-33 single-stage-to-orbit RLV technology demonstrator (video). Spiralling costs and changes in NASA's RLV thinking were blamed. Two completed X-34s and parts for the third were transferred to the US Air Force.