UC Berkeley (funded by DARPA) has created cyborg beetles guided wirelessly via laptop. These spy beetles were created with the intent of bugging actual conversations, literally acting as the "fly on the wall". The beetles range anywhere from 2 to 20 centimeters.
From Daily Mail:
"Using implants, they worked out how to control a beetle's take-off, flight and landing by stimulating the brain to work the wings.
They controlled turns through stimulating the basilar muscles on one side or the other to make the wings on that side flap harder.
The embedded system uses nerve and muscle stimulators, a microbattery and a microcontroller with transceiver.
DARPA's ultimate aim is to create cyborg insects that can fly more than 300ft to their target and then stay put until commanded to buzz off again."
Yikes. Big brother. Videos: