This colour sensing project is starting to get bigger than I wanted it to. However, I am learning a lot about the Arduino/Processing as I look for ways to accomplish my tasks. When you see my final code, I will have a bit of explaining to do.
I now have a relatively quick method of detecting MegaBlok colours, and will probably use a PhotoCell to improve read rates under different lighting conditions. Once I have done this, I would like to get the Arduino to do something in response to the colour. But let me get over step one.