I remember being a little twit and watching a tech show on tv with my dad and seeing the Pentium 3 dual processor boards. Obviously there were later boards that had dual xeons, or do have dual xeons, in a normal or workstation desktop.
Do we have anything like those still? I don't really hear anything about them if they do or they're in server environments and no one gives a rats ass. We care more about having 69 cores and 1337 threads at 50 trillion GHZ nowadays rather than experimental "What if we did this?"
The only motherboards like this at present are aimed at the workstation market. You could of course a build a very expensive gaming machine with one, but that would be complete overkill and likely not perform any better than the latest i7-6700 quad core CPU!