A company called Trackercam offers a cheap way to pan and tilt a digital camcorder up to 3 lbs in weight. It's a compact robotic base that interfaces via USB to a PC. A USB extension kit they sell gives the unit a range of up to 150 feet from the PC. A Windows SDK is available for custom programming.
They've offered versions of their base for lightweight webcams for years, but the heavy-duty camcorder version is new. It might have some applications in robots that need to capture high-res video.