A drone with a tele-doctor and defibrillator in 100 seconds?
There's a lot of excitement about the potential of autonomous drones, be they nimble quadcopters or longer-range fixed wing or hybrid aircraft. A group of students from Singularity University, for example, has a project called MatterNet working to provide transportation infrastructure for light cargo in regions of Africa where roads wash out for half the year.
Closer to home, these drones are not yet legal for commercial use, while government agencies are using them secretly.
Here's one useful idea: A small set of medical drones scattered around the city. Upon emergency call, they can fly, via a combination of autonomous navigation and remote-human-operated flying at the end, to any destination in the city within a couple of minutes. Call 911 and as soon as you say it's a medical emergency the drone is on the way. When it gets there, the human operator lands it or even sends it in a balcony on tall buildings with balconies. Somebody has to carry it to the patient if they are far from the outside.
When it gets to the patient it has a camera and conferencing ability to a remote doctor can examine the patient and talk to people around the patient to ask them questions or give them instructions. It also could contain one of those "foolproof defibrillator" modules able to deal with many kinds of heart attacks. They are already in many buildings but this way they could be anywhere. It's more useful than a taco.
The remote doctor could advise any medical staff who come, or give advice to the ambulance that's on the way but not getting there for a few minutes. If a medicine that can be administered by a layperson is needed, there might be some in the drone but a second drone could be loaded and dispatched within a few minutes as well -- that might take longer to fly but less time than an ambulance. You might not put any valuable medicines in the first drone to prevent people from summoning them just to steal them, though this might just happen for the valuable drone unless steps are taken to make that non-productive.
This should be combined with something I have felt is long overdue in the world of our mobile phones. People who are able to be on-call EMTs and doctors should have their phones updating their locations with a medical service while they are on call for such action. Then anybody with an emergency should be able to summon or get to the closest professional very quickly. (Of course there is no need to record this data after it changes, to avoid making a life-log of the doctor.) Nobody should ever have to ask "is there a doctor in the house?" 911 should be able to say, "There is a doctor 3 doors down, she's been notified." But the drone can always come, and bring a remote specialist if need be.
The other barrier to this is network dead zones. A map would need to be made of network dead zones and the drone would not fly into them, though it could fly through them. It would land just outside the dead zone and warn people not to carry it into one if the remote doctor's services are needed.
Someday, the drone could contain a winner of the X-prize "Medical Tricorder" contest with sensors to diagnose all sorts of conditions, and it might even eventually be a robot able to administer emergency drugs -- but the actual delivery and video feed is something we can do today.