Well I have a presentable application now. What I am writing is a post-fix (RPN) calculator using Cocoa frameworks. Cocoa adds so many features for free, that I can see building the application logic more than worry about the GUI part.
Well here you can see the main window of the Calc.app. As you can see, the window is a simple gui. The top is the number stack, and the bottom is the user entry area. In the entry area, the application will add 4 and 2 the multiply by 5.
After hitting enter in the entry area, the Calc.app places the result in the stack.
I should be able to get a Release version soon. Not that anyone reads this, but I would love feedback once I get it working.