wildcat captured-rail dolly
    This versatile captured-rail dolly can be configured in many different ways for a variety of special application shots. Since the dolly assembly is fully captured and counterweighted, the track can be positioned at any angle, from horizontal (like a standard dolly) to vertical (tower configuration) to completely upside down (underslung) or any angle in between. This allows you to carry a camera package straight up the side of a house, looking in windows, vertically up the center of a stairwell, across the top of a stage at a rock concert or to follow an actor scrambling up a steep embankment.. you get the idea. The wildcat can be motorized or grip-powered. It fits any Mitchell- mount head (like the Airhead). it can freestand on truss, or be strapped to trees, flagpoles, walls, large animals, whatever.