You can find Editra at http://editra.org.
The current version is 7.12 and it requires wxPython 2.8 to run. On my system, Editra is setup with Python 2.6 but I can run any version of Python through it (2.4, 2.6, 3.1, and even Panda 3d-Python 2.6). Where Editra really excels is by adding the optional plug-ins. Once installed, these transform Editra into a serious IDE for Python projects or simple code dissections.
Available for Linux, Mac OS X, and Windows
The project documentation explains everything from installation and configuration to adding the plugins, and by checking http://editra.org/supported_file_types you will see a list of other languages that Editra can be used to edit.
If your looking for a streamlined, functional, and flexible Python IDE, Editra is definitely worth a look.