Usb port can be made active to accept input from perpiherals
USB host mode for Droid - Hack a Day
This link explains how the setup wiring needs to be done. My friend and I added a separate input for an external battery. Doing this has made the device look a little cumbersome, but nonetheless, as the article mentions, the unit does work to some degree.
So far, I have been able to use a usb keyboard (pc only...mac keyboards do not work) to input asc text...no highlighting or other keyboard commands. I have also noted that if a usb flashdrive is inserted, the drive light powers on indicating that the unit is ready for data transfer.
That being said, it would appear that specific drivers need to be written for the device to work as a host...nothing other than the keyboard works now. But the possibilities for this seem rather intriguing especially in light of the very limited internal storage memory for apps.
I will attach a photo for you viewing pleasure in a little while. The cost of the unit you will see is somewhere around $30.00...lower if you can find the usb extender cable on line rather than in radio shack as I did...