... in looking at it, I'm reminded vaguely of the PICMG 1.x standard that had a backplane installed on the chassis, with the mainboard being essentially a plug-in card. (or the newer PC/104 standard, except that the form factor for the NUC is totally different than that.)
Edit: The only real reason I'm even looking at them is to determine expense, and size: I have a stack of old Dell Optiplex GX620s that occasionally get dragged out to be used for Artemis as bridge stations, and they pull a lot of power and dump a lot of heat for what they actually do. (they are all P4 class machines). I'm thinking of swapping them with either NUCs or compute sticks, although the latter would probably work out better as I could build them (and their VGA adapters) into the base of the touch screens I have.