I started thinking today about doing a blender pot and came up with the idea of a little wheel, rather than a knob, that I could roll back and forth to adjust the blend amount. The wheel would be recessed and only a small portion of the wheel would be sticking up. Then I could just roll my finger over the wheel to adjust. I don't know how else to describe what I am thinking of and I hope it makes since. Does such a thing exist?