Something along the lines of a Serta mattress with it's "sleep number", so you could inflate your handlebars to your perfect "ride number" for cushiness or firmness?

I got to wondering after wrapping my new trekking bar in an old inner tube, and thought "that would be a great idea!" Since all my great ideas come in two flavors, "Already done by someone", and "stupidly unworkable", I was wondering if someone had done the "already done" part.