A convergence handheld device would be all of these things: a cell phone, a TV, a radio, a computer, a GPS navigation system, a wireless network device, and a digital still/motion camera. A cell phone, TV, radio, GPS navigation and wireless networking all involve radio or microwaves. An emerging wireless standard, WiMAX, allows wireless communication over a range of 8 miles at Ethernet speeds. If you have a WiMAX link from a handheld computer to a desktop computer system, then the desktop computer can provide the TV, radio, and telephone functionality. Some people are trying to use the known locations of wireless access points to perform a kind of triangulation similar to GPS navigation, but that would work best in urban areas. If a projector or external monitor had wireless capabilities built-in, then there would be no need for a separate monitor adapter.
A proposed specification for the next generation of digital monitor interfaces uses differential signaling on a reduced number of wires, sort of like a high-speed serial connection. Perhaps USB2 or the next generation of wireless USB could be made compatible with that. A company named Rambus has a high-speed signaling technology called XDR which would seem well-suited to handheld devices, because less board space and a fewer number of communication lines are required for high bandwidth data flow with XDR technology.
