It's not quite what you think, but it is pretty close. The U.S. Department of Defense's research and development division is working on a radio-controlled aircraft that looks and flies like a hummingbird. The robotic hummingbirds will be able to discretely enter areas where people would not be able to go without being detected and will look so realistic that people could easily be fooled (watch the video below to see a prototype in action). It's easy to imagine how this type of technology could be useful for numerous kinds of spy activities.
While I definitely think the idea is cool, is it absurd for me to also worry for hummingbirds? Once robotic hummingbirds are out and about, will people view hummingbirds with fear and suspicion rather than with joy and wonder? Any thoughts you have are appreciated in the comments section.