Tokyo Cabinet and Python - Tokyo Cabinet is a scalable key-value database that can be used in high performance applications, including Python.
Using MongoDB in Python and PHP - MongoDB is a no-relational document database. It main features are high performance and advanced features compared to plain key-value stores.
MongoDB data management in Python - Description of the pymongo driver and data management in schema-free MongoDB database
Searching multimedia sites in Python using public APIs - Search for video clips on YouTube and Vimeo, find slides on Slideshare, or documents on Scribd using Python and RESTful web APIS
Aggregating and searching for developers projects in Python - Gather projects from bitbucket.org, github.com and code.google.com that match given search term using Python script
Using Guardian OpenPlatform API - Guardian Open Platform is a new API from The Guardian for accessing it's publications, news and articles

RkTaggy - example Google Wave robot - RkTaggy is an example Google Wave robot written in Python. Get the source code, and read how RkTaggy is built.
Embedding Waves on web pages - How to embedd public Waves from Google Wave using robots and JavaScript code snippet

GUI - PyQt4

pyxdg - freedesktop.org specifications support - Handle application menu, file MIME types, recently used files, .desktop files and more used by Linux/Unix window managers.

Info

Harvesting data from websites using WebKit and PyQt4 - part 1 - Example use of Qt WebKit module to harvest data from complex web pages
Harvesting data from websites using WebKit and PyQt4 - part 2 - Extracting data from parsed HTML code of a website with WebKit and PyQt4
Harvesting data from websites using WebKit and PyQt4 - part 3 - Gathering final data for ad urls (final page title and URL) using PyQt4 with QtSql module.

Building standalone MS Windows apps with py2exe - How to make standalone Windows applications from Python and PyQt4 scripts using py2exe.
Building Mac OS X applications with py2app - How to make standalone Mac applications from Python and PyQt4 scripts using py2app.
PyQt4 in Maemo Fremantle - Installation and configuration of Maemo SDK (Nokia mobile OS for N900 and other phones) and PyQt4 libraries.
WebKit in PyQt - rendering web pages - qt-webkit provides WebKit API in the Qt library and it can be use in PyQt to render web pages
PyQt events - A description of Qt events, and QListWidget example of handling mouse events.
QtSql in PyQt4 - handling databases - Overview of QtSql classes in PyQt that allow managing databases and grid integration
QGraphicsView and QGraphicsScene - Description of widgets for visualizing 2D data (images etc.)
QTimer - making timers in PyQt4 - Description of timers available in PyQt4

QScintilla2 and PyQT4 - Adding widgets for programmers to PyQt4.
Making PyQt4 widgets with SIP - Tutorial on making PyQt4 widgets from Qt4 widgets using SIP.
PictureFlow - listing images in PyQt4 - PictureFlow - extra PyQt4 widget
Rendering PDF files in PyQt4 with pypoppler-qt4 - Description of pypoppler-qt4 - bindings for Poppler library.

Pylons

Psyco - speeding up Python - Installation and usage of Psyco module
Python, C and C++ efficiency on JPG thumbnail creation - There are several tools to make thumbnails: Imagemagick, PIL ,GD, and also EPEG/libjpeg. And we also can make Python modules from a C Epeg library and compare how much slower it will get if we use it from a scripting language like Python.
Pylons benchmark on various servers - SCGI and FastCGI, Cherokee and Nginx
Lighttpd and Cherokee Benchmark - Pylons and SCGI
Simple Python Frameworks Benchmark - A simple httperf benchmark
cherokee and lighttpdf Django SCGI benchmark - A small test
Plain Files - server I/O benchmarks - How reading plain files imact performance