I've built a tool that lets you run your Python code as you type it. For example, this code draws a 100x100 pixel square.
When I change the forward distance to 50, the square immediately changes. I don't even have to save the file.
In this tutorial, I'll demonstrate two things. Live turtle graphics that make a fun learning tool, and a live coding display that can be used with regular code to show you what's happening inside it. To try it yourself, visit donkirkby.github.com . To see it in action, watch my demo video , or read on.