S90 Control Dial Solution --> Asking for $ 10.00 (US $ 9.20). (New never been used, because I sold my S90, so this control dial solution will do me no good)
If you have questions, feel free to email me.
One thing that spoils the otherwise excellent interface of the Powershot S90 is the rear control dial. It turns too easily and the cluster of buttons inside and surrounding the dial are too easily pressed resulting in undesired changes, often not noticed until it's too late.
The solution - a small laser-engrave Delrin™ ring with an adhesive backing that surrounds the dial which eliminates unintentional dial rotation and button presses.
How it works: This simple device provides a raised surface that protects the control dial and buttons from unintentional activation without hampering their normal use. You can even hold the camera with your thumb directly over the dial without activating any buttons or the dial.