Just from the headline, I said to myself, "sounds like some kid discovered peltier junctions and LEDs and the media decided to act like she's invented something," which was exactly right. Good for her, she's learning and experimenting, and that's a great thing, but let's not get carried away with our portrayal of how amazing it is.
Think back a month or so to the girl who "invented" a new way of charging cellphones in 30 seconds using capacitors. The sensationalism of that story was so over the top, I had non-technical people sharing the story with me on Facebook with breathless comments about what a genius this kid was and looking forward to this fantastic tech being available in all of our cell phones. Was it anything like that? No. It was a kid experimenting with well-understood technology and learning how things work, and there was no discovery or invention of anything non-obvious to any actual engineer. I don't want to detract from her industriousness or enthusiasm for learning, but when half the world is convinced she's done something notable enough to get her on the talk show circuit, something is wrong with the reporting.
I'm cool with A or C. B seems lame.
It might, however, be awfully useful in a stiatuion where there is no ambient light available at all, or where equipment needs to be light and very simply constructed. Perhaps something like in an emergency kit in case of a mine or cave collapse. Or in a situation with very adverse operating conditions, like a desert. Moving parts (as for a hand crank torch) would be a liability in an environment with omnipresent particulate contamination.
Could a 15 year old child invent safety equipment for the trillion $ mining corps. Of course not.
People with 4 year degrees in engineering have as much commitment and inventiveness as children and money to boot. Plus a fully developed brain.
As is always the case child age x invents new way to do blah, invents object blah they of course haven't.
As a tired cliche does it have a place on HN. Is this site aimed in part at children is the question?
We've know for years washing your hands in hospitals saves lives.
And we've know for years people are not doing it. Even just putting up signs helps an amazing amount, but even this isn't done.
Cause it's a really hard problem.
How does one improve the issue? Some hospitals are trying cameras, ranking deaths in hospitals, rfid tags tracking people making sure they wash.
I'm willing to bet even though the checklist above is pretty close to proven most hospitals don't use it.
[edit] http://online.wsj.com/article/SB1000087239639044462010457800...
The hypothesis was approached from both the theoretical and experimental side.
I'm thinking backup light source for camping, spelunking, power outages at home... just enough light to find a path when there is no other light.