So, the prolonged blackout in lower Manhattan and elsewhere has gotten me thinking about what would be the best Uninterruptible Power Supply (large battery, more or less) to charge USB devices (mainly phones) and laptops. I know there are various USB battery packs on the market, but these are portable/smallish, and don't hold THAT much charge, so I was looking at the huge APC/Cyberpower/etc units. Three questions: 1) There appears to be a distinction between sine-wave and sine-simulated power output. Does either matter for laptop power adapters? 2) Anyone know of any units that have USB power output ports? I figure these would be more energy efficient to charge USB devices instead of using the device's AC adapter. (Direct battery DC =>> USB DC, rather than battery DC -> UPS AC inverter =>> device AC adapter -> USB DC). 3) Is this even a good idea? Is there something better than a big UPS for such an application/emergency preparedness? (While keeping it more or less simple - no generators or overly expensive solutions...) Thanks..