The "xappy" module is an easy-to-use interface to the Xapian search engine.
how to play with Xapian and Python.
david petar novakovic: attempted axiomatisation » Code: Full text Delicious index in python with xapian and twisted
Your own personal bookmark search engine in 100 lines of code.
Xapian, FeedParser, Twisted and a few lines of code. Very neat hack.