Inspecting antennas – by radio controlled quadcopter!
Some years ago I went to a BBQ where someone had a wi-fi controlled quadcopter remotely controlled from an iPad. It was very impressive with its on-board cameras for navigation and filming what was happening down below.
I see AE5X has a video showing the inspection of his antennas (from above) using one of these. My antenna farm is trivial by comparison and can be pretty well examined at ground level.