IBM Model F AT
Probably could use a little cleaning but this is the ultimate buckling spring board in my opinion and is finally in my possession. Capacitive PCB for a sensing assembly instead of a membrane like the Model M's buckling spring mechanism. Not that the Model M is bad, this just lot a smoother, more tactile and louder. Only mild irritation is the placement of ESC since I'm a vi user.
My apologies for the condition of the desktop itself. It's a fifteen year old big box store particle board desk and the veneer is really letting go. A future project will likely be building a new top for it or outright building a whole new desk.