Kill the iMac. It fits the wild computer speculation theme. And, it's not entirely insane if we only kill it as we know it, not wholesale genocide. Replace it with a line of "Mac Mini type" boxes with no I/O to speak of, except for wireless, a power plug and thunderbolt ports. Then, redesign the Apple displays to supply power to the CPU, like it does now for the laptops, but with more power for desktop biased machines. Put all the I/O breakout into the display: audio, mic, SDXC, USB2/3 FW, and TB (though it sounds like doing it this way might require a smidgeon of proprietary engineering, since TB is supposed to terminate the device chain.) You could always put two ports on the mac boxen, so they live more easily on non-Apple monitors)
Make the monitors good: big, wide and full featured, for pros and consumers alike. Stuff like SWOP certified matte screen options for pros, built-in high quality audio (20 watts or so of clean power with reasonable base extension - down to 60-80hz or so, like what you might get from a decent book shelf speaker), airport antennae, iSight camera, all the aforementioned I/O... Maybe even put the optical into the display, programmed to work as a bluray/DVD player even when not connected to a Mac, or when the mac is off.
Sell Displays and Boxen bundled and seperately. The boxen should span a range of prices an specs. All sealed except for RAM an HDD. All simple 1 or 2 plug connections. They might start popping up all over the place. Server farms, home theatres, custom installations in A/V, production, computer control, mobile/auto/boat/rec etc...
Still call it the iMac. No display, but sold on the same, one plug and you're off notion as the original. OK, maybe its a little insane...
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