Ever needed to determine whether an email was sent from a Django project? I made a Django application that does exactly that: django-email-log.
I got the idea from a StackOverflow answer and I decided to make a real application out of it. All emails are stored in a single model which can easily be viewed, searched, sorted, and filtered from the admin site.
I used test-driven development when making the app and I baked in Python 3 support from the beginning. I found the process of TDD for a standalone Python package fairly easy and enjoyable.