Display link 7" inch usb monitors

Thanks to Adrian for this (good one) these devices that plug into a device via usb (potentially mini usb) for both display in and power. It brings the idea of small device (mobile) that one can easily plug into a larger screen much closer . Seems a really good development
http://www.itpro.co.uk/608223/mini-7in-displaylink-usb-monitors-introduced?CMP=NLC-Newsletters

stick a key board on it and we are getting near the one device model for many users. How long before the bring out a cable connection for the Iphone ?