Communicating with a device via USB port , is it possible? I am new to Android Platform and I Like to know whether it is possible for an Android device (App) to communicate with Linux/XP system via USB port for 2 way communication. If yes how can it be done? 

What I want to achieve: I have a PC running Linux and I want to write a small App in my Android device to send and receive data from PC via USB.
Android Devices as USB Hosts has been a point of interest for all the developers. Until the Android's HoneyComb OS (OS 3.0), there have been no signs of possibility.
The latest HoneyComb API (OS 3.1), however, seems to provide possibilities to support Android devices being used as USB Hosts. An API has been included for the same.
Therefore, though as of now very few Android devices support the USB Host capability, it will be possible in all the upcoming devices.