I have seen a few questions about this in various places, and perhaps someone has already answered it. But for those who are interested, not only is it possible to use a large-capacity, unpowered external USB hard drive, it's very simple. The trick is that it needs to be formatted in FAT32 format. Windows will not let you format large drives in FAT32, but you can use this handy tool to accomplish it. Ridgecrop Consultants Ltd 500Gb tablet? Take that, iPad!