Blender
Blender is a great open source 3d modeling software, which uses Python for scripting. To debug Blender Python scripts with Winpdb you need to use the embedded debugging technique.
However, due to a bug in Blender, Winpdb will not be able to show the source of the script if it was launched directly from the Blender dropdown menus, or scripts window.
For Winpdb to be able to show the source of the script you need to first open the script in the Blender text editor window and then launch it from there with ALT-P (press while in the blender text editor window).
Winpdb - A Platform Independent Python Debugger