This is the reason that Sony and Polyphony Digital will always command an ultimate level of respect amongst the technologically obsessed. The Gran Turismo makers have synchronised four PlayStation3s running GT5: Prologue and merged the video outputs to produce what must surely be the world's first videogame running at an astonishing 240FPS. No current generation display can handle this. Instead, Sony demoed its prototype 19 inch nano-Spindt FED screen capable of this supreme refresh rate.
The synchronisation is achieved using the common or garden LAN ports on each PS3. All four consoles are pushing out 1080p at 60fps, but on the 240fps display, each frame is being queued to be displayed in an astonishing 4.2ms. Personally we had trouble believing this was even possible until Polyphony showed it working over at granturismo.com.
The original report also talks about using the same network to generate 3840x2160 realtime gameplay with each PS3 outputting a quarter screen of 1920×1080 (though native resolution of GT5 is actually 1280x1080 expanded outwards). Now this is obviously impressive, but we've seen these resolutions already on PC gaming. But a real, working 240Hz display, ingenious powered by present day consumer gaming technology? Now that's something else.
The only real question mark left in our minds is the 'synchronise and merge' mechanism. Um, how? The best guess would be four HDMI ports on the prototype screen itself, or else a custom video processor handling all four feeds and generating one bespoke output.