A friend of mine got a new K3 a few weeks ago, and when I saw her in town today, she flagged me down to ask a Kindle question. She had to relocate for awhile due to flooding, and, in doing so, misplaced her wall charger for her K3. She tried to charge her Kindle via the USB port on her computer, but it wasn't charged after a couple of hours. She said the light was orange, which (at least to my way of thinking) indicates that the unit is plugged in and hopefully is charging. I told her to leave her K3 plugged in overnight. If her computer happens to go into sleep mode or hibernation, would that cause her K3 to not charge? If this doesn't work for her, I made the mistake of saying that I have a spare wall charger for those times that I'm afraid I'll lose my other one. Of course, if I loan it out, I'll probably misplace MY wall charger.