Very interesting. There are so many USB charging standards - I had been thinking that it should be possible to construct a universal USB power converter. (Even

Very interesting. There are so many USB charging standards - I had been thinking that it should be possible to construct a universal USB power converter. (Even in the case where the charger can't supply the watts the device wants, you could accumulate some energy in a small battery large cap and charge intermittently). But I suspect the reason it hasn't been done so far is liability - there are bound to be a few devices that don't play ball and blow up.