Chloe - a chatterbot with charisma. Learns from experience, and speaks any language you teach her. Perhaps even useful, but surely entertaining.
Jester is a gesture / stroke recognition framework for Python, written in Python.
Verbti - Email client for the blind
pyDATR is an implementation of the DATR language written in Python and usable as Python library. It provides a means for persistence and some extensability with Python functions.