Here's a small hovering spybot from Germany with a high-resolution video camera onboard:

"The AirRobot, an exceptionally light and quiet video probe capable of autonomous flight, can be flown without any pilot experience...the pilot can fully concentrate on his exploration mission. Due to its silent electric drive, its diameter of one meter and its weight of less than one kilogram, the AirRobot can also be used in residential areas. Our customers include mainly the police and the army."

-- Air Robot website

It could hover outside your apartment window or over the trees in your backyard and you'd never know it was there. It even has infrared capability in case you forgot to leave the lights on. Isn't technology wonderful?