I'd like to suggest a Faces numpad as a potential product. The current Faces kit comes with a calculator keyboard and includes keys like +, -, /, x, %, M, AC, etc, but this is not very handy. They are only useful for making a calculator, so this is a single use case.
A numpad with the 10 digits + OK + Cancel + (maybe?) backspace buttons would be more handy and flexible, like for a small payment terminal.
Basically, remove the top row + right column of buttons and you'd be 99% there. This would allow for bigger buttons.
- Also, make the numbers on the keys white, so they are easier to read on the black buttons. Especially in dark rooms, like a bar.
- The OK button should be green.
- The Cancel button should be red.
- The backspace button (if you like this button) should be yellow/orange, or it can be dropped if there's no space left.