Once you've cleared the $25k or so in your budget that it will take to snag one of Sony's 4K VPL-VW1000ES
your next problem will be finding some 4096x2160 res content to view on it. While showing off the new beamer for its Japanese audience at CEATEC today, Sony announced the PS3 will get a firmware update around the beginning of 2012 that will allow it to natively output 4K stills. There's a PlayView "visual magazine" already available on the PlayStation store in Japan that supports 4K and 3D, but this update will bring super high res viewing of your vacation pics, or any other high res image files you can snag, to the living room. While your friends will no doubt be impressed by the museum-quality art gala you're now capable of hosting, we're starting the timer for 4K video sources -- if we don't hear anything concrete at CES then we'll be incredibly disappointed.
Sony VPL-VW1000ES 4K projector