I just bought one of these, primarily because of the positive comments here and a good eBay price. Since it's marketed as a backup device to use when traveling, I was dismayed to find that it came with its own wall wart power supply/charger. The last thing I need on a trip is another charger to haul! So here is the fix: Input power spec is 5volts, 2 amps. This is the most common tablet USB charger spec as well, so it is just a matter of cutting the mini-USB or micro-USB plug off a standard USB charging cable and soldering on a plug that suits the UDMAII. For a cable, I recommend the monoprice 28/24AWG cables (http://www.monoprice.com/Category?c_id=103&cp_id=10303&cs_id=1030307). These have 24 gauge power wires and handle the 2 amps easily. Many other cables I have tested do not. The plug to the UDMAII is a "Philmore #240." This is an EIAJ-02 plug with a 4mm od barrel and a 1.7mm id for the positive pin. Catalog page PDF here: www.philmore-datak.com/mc/Page 63.pdf Use a meter to verify the cable voltage and polarity. With the monoprice cable that I used, the red wire connected to the center conductor of the Philmore plug. The black wire and the shield connected to the body of the plug and the other two wires were cut short. Strain relief can be a concern with these little plugs, so after soldering and testing, I used some 5-minute epoxy to sort of goop all the wires and connections together. Then when I screwed the cover onto the plug, I turned the assembly vertical and put some more epoxy in at the top, hoping it would drain down towards the wire end of the cover and further reinforce things. Finally I put a short length of heat shrink tubing over the whole thing to keep the wire from bending sharply at the plug. So now I only have to carry a 1 ounce cable that takes no space instead of a bulky, dedicated charger.