The USB hub's power is supplied by a 110v power pack. You plug the power supply into the wall socket, and that will supply the hub. You'll need the hub when plugging too many USB's into the computer at the same time. The computer power supply can't handle the load, and someting will give. It's just basically an added power source to protect the 'puter.
My hub has 4 USB ports. A fifth port goes to the computer for data transfer. The 110v outlet power, powers the hub's 4 ports.
Actually, if you only power your ciggi from a hub, you won't have toconnect it to the computer, since the ciggi dosen't transfer data. And if that's the case, just pick up a 110v to USB adapter from Best Buy, and go directly to the wall. that eliminates the added cost of a hub.
Cheers;
jd