If I am reading this discussion correctly, the USB port on the n800 can't be used to charge the n800. I have a USB charger that came with my i-Blue 737 GPS receiver. It outputs 5v at .5 amp. Too bad I can't use it. What I am really looking for is something called a battery box that hold 4 AA batteries and is used as an emergency charger for a mobile or PDA. I found one at Paden.com that serves this purpose for units that charge through the USB port. The idea is that you insert 4 AA batteries and the device to be charged sucks juice out of the batteries and charges the internal battery. This would come in handy if you were off the grid on a canoe or hiking trip. The link for it is http://pdaden.com/shop/cart.php?targ...ategory_id=301 Has anyone heard of anything like this with a 2mm plug? -- rhackenb