to tie up Ghosts
The Ghost Rope was a gizmo that featured a tiny helictoper like attachment that could lift off from a handheld holder shaped not unlike the lower part of a handgun. The helictopter was remote controlled by the holder, and dragged a powerful rope behind it.
By encirling an intended target, whether it be alive or dead, the Ghost Rope could either grab an object, for instance Sir Trancelot's Trance Lance, and pull it out of the bearers arms, or encircle an antagonist completely, catching it with the rope.
The Anti-Gravity device was first used in the episode Like Father Like Son.