There are many interesting ways to pull heat away from a processor. You can submerge your device in mineral oil or even phase-change fluid (such as "Novec"). You can push cool fluid up to the thing that you are trying to remove heat from and then pump it away through a radiator. If using air, you can make use of vapor chambers and the convection current formed as devices heat up. The goal is to abuse one or more interesting material properties to store energy and move it somewhere else.
Image Credit: HT4U.net
Or you can just have an obscene, gigantic mass of metal with more fins than the NHL. According to FanlessTech, these are three heatsinks that are not yet available (and may never be). Two of them have three towers, connected to the base by heat pipes, and the last one has four.
Image Credit: ExtraHardware.cz
Personally, I would be a bit uncomfortable about buying a PC like that unless I needed absolutely silent or top air cooling performance. The amount that it hangs over RAM or nuzzles against add-in boards seems sketchy to me, especially if you need to swap a DIMM or two at some point, but I always use stock coolers at reference voltage and frequency so what do I know?
Image Credit: PConline.com.cn
Yes, that would be a regular, ATX motherboard.
When will these prototypes become available? Who knows if they even will. Still, if you have a need for cooling solutions that are a little over-the-top, you might be able to get your hands on these some day. There's nothing wrong with adding more mass and surface area, rather than doing something fancy. It works, and it probably works really well.