Does anybody know what options there are for an on thre go usb selective file copier? By that, I mean, a device like Macally's Syncbox II.[http://www.macally.com/spec/usb/input_device/tablets.html]
I'm looking for something that can selectively transfer files, with an LCD, relatively small sized (handheld or smaller), and the option to run off batteries. So far, all I've found are blind-copy devices, most of which run off an AC/DC input. The reason I'm searching for this is because I've recently got a psp, and would like to transfer files from a removable HD to the mem stick back and forth while on the go, and make boring trips more enjoyable. Anybody got some info on this?

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