i use a laptop with powered computer speakers, feeding a mounted 15 inch computer screen. and a tv usb tuner that does digital tv. i can do split screen and surf the internet on the laptop screen while the tv is on the 15 inch monitor
i have decent sound, and switchable power draws. the wife also plugs her ipod into the computer speakers
the monitor draws less than 3 amps, the laptop can be on battery and the speakers dont draw much they came with a 12 volt 250 milli amp walwart.
the other nice thing is i can feed chart data to the bigger screen.
it works well for what i want and need