One of the sorry things about living in the modern age is how so many technological inventions and discoveries seem to serve only for the police and military sectors.
I look at this nifty gadget and immediately the needles on my cool-o-meter gauges all start a-twitchin', I can see some very practical civilian applications, such as, search and rescue and.. well, let me think..
On the other hand, think of all the not so nice things you can do with this. This will never reach the consumer, or if it somehow does, it will be quickly banned. It's only fun to use something like this if you are the one at the controls.
First of all, you might as well forget the quaint notion of privacy if a little hummingbird can fly up to your sixth floor window and watching you as you watch somebody you barely know changing clothes in some other part of the building. One minute I am sleeping with my mouth hanging open and a trickle of spittle on my cheek and the next minute, I am a YouTube meme.
More seriously, consider the frightening military applications. (Perhaps I missed my calling in life but I can quickly come up with a lot of scary scenarios involving this pet.). Spying is one thing, but think of the many offensive capabilities. Add a tiny vial of nitroglycerine and you have a mini-drone. Still, worse, add a syringe and some nasty bug and you have a more subtle assassin. That's not THAT far out of the realm of possibility, you know.
In fact, this device is probably far behind what we will not see. That would be much smaller and work as a swarm. Not hummingbirds, my dear, flies.
The next James Bond will be about 3 inches tall and fly around like a hummingbird.