Just below a half-opened garage door a tiny device can be seen at the feet of someone lurking in the shadows. It looks like a blue dragonfly. Then its miniature wings begin to flap as it slips under the door and darts along the street. After rising through the air it stops to hover outside the window of a building several storeys high. There is an opening on the roof, and it slips inside. As it flits from room to room its video-camera “eye” transmits pictures to a screen on a remote-control unit strapped to the wrist of its clandestine operator.

　　This is not a scene from a James Bond film, in which 007 tests a new device from “Q”, but an animated video produced by Onera, France's national aerospace centre, to explain REMANTA, a project to develop the technologies needed for miniature robotic aircraft. More bug-like flying devices are being developed in other research laboratories around the world. A few are already small enough to be carried in a briefcase; others are the size of a jet fighter and need a runway for take-off.