I'd love to hear from someone that has actually used the RATOC USB Host adapter. While I have seen reports of it working, and places to find drivers for various things, most seem relegated to W?BIC scenarios.
My concern would be the ability for the adapter to supply power to the USB device, hard drive, USB thumb drive, keyboard, etc. While I am sure it does supply some power, I don't imagine it would power an external hard drive, or if it does, not very long. That means you need some sort of power source, whether plug in, or battery. Battery sources tend to be a bit bulky. So you wind up with a PPC, a hard drive, a battery pack, and a jumble of wires to hook it all together. That might be an OK system if you are cobbling something together to get pictures of an SD card onto a little hard drive. For portable file storage, like music or videos, or GPS maps, it would seem a bit ungainly to me.
You can get a 4G microdrive for under $200 easily (
http://www.pricegrabber.com/search_g...terid=5555167/) If you subract out the $140 for the RATOC card you are thinking of getting, you are out $60 for a pretty significant amount of storage. Yea the uDrive uses battery, but the convenience compared to the external drive kludge has to considered. It doesn't have to stay in all the time, and is a lot easier to carry seperatly than the Ratoc, drive, power source combo.