Wii Paint is a desktop application I wrote in Objective-C. It works in use with a Wii Remote, a battery operated IR Sensor Bar, and DarwiinRemote, an application that maps keyboard keys to Wii Remote buttons.
Keyboard Keys for WiiPaint Desktop application:
n is for new canvas (clears the screen)
b goes back in the array of colors
c goes forward n the array of colors
Using IR mode will map mouse movements to Wii Remote movements with an IR Sensor.