Albatross is a small and flexible toolkit for developing highly stateful Web applications. It provides browser-based sessions via automatically-generated hidden form fields, server side sessions via a session server or file-based session store, a powerful and extensible templating system which promotes separation of presentation and implementation for improved program maintainability, implicit handling for pagination of sequences and tree browsing, template macros to allow repeated HTML and special effects HTML to be defined in one location, and lookup tables to translate Python values to arbitrary template code. Applications can be deployed as either CGI programs or as mod_python module with minor changes to program mainline. Custom deployment can be achieved by developing your own Request class.
MP3OCD is an MP3 categorization program written in pure Python. It differs from traditional MP3 categorization because it queries freedb.org to obtain information about a set of MP3s and automatically renames them to their appropriate names. It also sets up a set of symlinks to make burning easy.
MayaVi is a free, cross platform, easy-to-use scientific data visualizer. It provides a powerful GUI to ease the visualization process. It is written in Python and uses the Visualization Toolkit (VTK) for the graphics. MayaVi can be scripted from other Python programs and also from the interactive Python interpreter. MayaVi includes the VTK Pipeline browser. The VTK Pipeline browser is a Python module (vtkPipeline) that enables one to view and configure the objects in the VTK pipeline graphically with a Tkinter-based GUI. The browser should work for any Python script that uses VTK. MayaVi also provides classes to pickle a VTK object and a simple class documentation browser.
Papercut is a multi-threaded NNTP server written in Python. Its main objective is to integrate existing Web-based message board software (Phorum is one of the supported ones) with a Usenet front-end. However, its extensibility enables developers to write their own containers for the storage of the Usenet articles (messages). That means that the code is extensible enough that you could write new containers to integrate the news server with other Web message board projects or even other ways to store the messages.
QuantLib is a cross-platform, quantitative finance C++ library for modeling, pricing, trading, and risk management in real-life. It is also wrapped as Python/Ruby/Scheme modules. Extensions for Excel, R, and Mathematica are available. Other such extensions are under consideration. QuantLib offers tools that are useful both for practical implementation and for advanced modeling. It features market conventions, yield curve models, solvers, PDEs, Monte Carlo (low-discrepancy included), exotic options, VAR, and so on.