Phlatscript – Sketchup to G-code
This is a plugin for Google Sketchup that generates G-Code from 2D drawings from the folks at Phlatboyz.com. It is very limited in what it can do, but many people will like the familiar interface of Sketchup.
Below is a video of what it can do. The code is open source and can be obtained from their forum here. You need to register on the forum.