Lyndsay Williams of Girton Labs brings us the Sensesurface control interface –
Applications that would normally use a mouse or Qwerty keyboard can be now controlled with traditional knobs. The scroll bar on the right hand side of your computer screen can be controlled with a real slider button. SenseSurface can be used with most laptops with a USB input. The sensing knobs have a custom designed movement sensor to determine position within approx 180 degrees with a 10 bit digital output, linearity typically 1%. The magnetic knobs can be removed and repositioned immediately by picking them up and moving to a different part of screen. A unique sensing x/y matrix is attached to the rear of the laptop screen to detect the control’s position.