This is the one I was thinking of.. https://arstechnica.com/gadgets/2014/01/new-microfluidics-panel-could-add-physical-buttons-to-a-touch-screen/ https://arste

This is the one I was thinking of.. https://arstechnica.com/gadgets/2014/01/new-microfluidics-panel-could-add-physical-buttons-to-a-touch-screen/ https://arstechnica.com/gadgets/2014/01/new-microfluidics-pa...