A very nice project for generating CNC specific gcode:
It can use a few usability tweaks but there is a lot of potential, check for example the 3D simulation.
It also has a link to [url=http://chilipeppr.com/]Chilipeppr[/url], another very nice project. Which is a webbased GBRL controller. It has a fancy 3D view, simulator and can even connect to your webcam using WebRTC.