French company Papoo recently posted the video above to show-case their proximity switch. In short, a switch that you don't even need to touch. Could be ideal for those struggling with the amount of force needed to operate a traditional switch.
There's plenty of mounting solutions on offer, detailed in part at the OneSwitch Accessible Gaming Shop, such as the superb Trabasack and Flexis.
Update: Of historical curiosity, Zambette Electronics of Southend-on-Sea, Essex used capacitive switches with their 'System 7' devices in the 1960s and 70s for environmental control and control over electronic toys.