I am starting to collect examples of applications that use PyGreSQL. So far I only have a few but if you have an example for me, you can either send me the files or the URL for me to point to.
The A PostgreSQL Primer that is part of the PyGreSQL distribution shows some examples of using PostgreSQL with PyGreSQL.
Here is a list of motorcycle rides in Ontario that uses a PostgreSQL database to store the rides. There is a link at the bottom of the page to view the source code.
Oleg Broytmann has written a simple example RGB database demo