What is the best project structure for a Python application?

Imagine that you want to develop a non-trivial end-user desktop (not web) application in Python. What is the best way to structure the project's folder hierarchy?

Desirable features are ease of maintenance, IDE-friendliness, suitability for source control branching/merging, and easy generation of install packages.

In particular:

1. Where do you put the source?
2. Where do you put application startup scripts?
3. Where do you put the IDE project cruft?
4. Where do you put the unit/acceptance tests?
5. Where do you put non-Python data such as config files?
6. Where do you put non-Python sources such as C++ for pyd/so binary extension modules?