Python
I like Python a lot, even if I can't claim to be any good at proper object-orientation such as Python appears to be based around. It's simple, it's elegant, it's clean... and most importantly, it's very powerful. Here's what I've managed...
SpamCubed, a University mass mailer
SpamCubed (for Spam3) is an update of PyFishBox, one of the first programs I wrote in Python, originally to send out a generic list of birthday invitations. Using the University mail server, it sends out e-mails without making it obvious that a large list of people has been targeted. Just as usefully, it is capable of running addresses through the University's online contact search (to verify that they exist) before sending. I wrote it to help me send out lots of birthday party invitations, making sure I hadn't misspelled any names - however, an unfortunate side effect of the trusting nature of mail transfer protocols is that mail can be 'spoofed' and appear to come from virtually any address.
It has a fully-fledged command-line interface and can load and save data from files. It is, however, very specifically designed for Oxford University and University-style email addresses, so may not be suitable for other applications.
Licensed under a BSD-style license.
Download/ View Source - it's labeled with an additional .txt extension to allow it to render in a browser.
CGI Obfuscator
Use the CGI obfuscation methods! The obfuscator was something I initially wrote in Safeperl, to try out on University webspace, because I was playing around with simple encryption at the time. A little obfuscation can be helpful sometimes, so I've ported it to Python and put it up here.
FerretBrain
The back-end for FerretBrain.com was written by me. Entirely in Python. Being the open-source fanboy that I am, I looked around the web for solutions that would fit my bill, and then modules that would fit my bill, and found just one: the SpamBayes project's PyMeldLite templating engine. All the other parts were written from scratch.
Viverra
Having failed to find an appropriate solution for FerretBrain, along with a friend I wrote my own framework, the website for which is here!