I don't know if the current of the reader goes both ways. When the reader is connected to the PC, it gets charged, but I don't know if anything attached to the readers usb port will get any voltage (which I doubt). Good idea though.
But I won't try as I would have to change the connector.
There are several Battery-USB adapters out there, I just don't know if I can get them in Germany in a store. If not, I'll go and get a battery compartment and a USB port and build my own casing. I'm really looking forward to that. If I get it done, I'll also post an instructable on instructables.com. There you can find a leather pouch and a cup holder I made and posted so far.
