Not quite the same as a pen plotter, but the Maslow CNC http://www.maslowcnc.com/ takes a similar approach to CNC (no reason you couldn't replace the router with a pen), but with a near-vertical work surface. OTOH I guess an 'ordinary' CNC is the same base principle as a plotter, just with more moving parts and another dimension. As are 3D-printers (the extrusion type, at least)
Shameless self promotion but here's one I built: https://www.markjgallagher.com/projects/#/utsushi/