"Be seeing you!"
reports this morning that a large black ball, originally designed by Swedish scientists for use on Mars, may be used as a high-tech security guard. Capable of traveling at 20mph, this robot ball can detect intruders with both radar and infra-red sensors. Once alerted, it can call for help, sound an alarm, or pursue the badguys, taking pictures all the while.
This news reminds me of Rover (pictured above), the robotic weather balloon security guard from the classic "Prisoner" TV series of the 1960s. Rover made sure all the numbered citizens of the Village -- particularly Patrick McGoohan's No. 6 -- didn't leave town.