BleachBit deletes junk to recover disk space and maintain privacy. It rids your system of old junk including cache, Internet history, temporary files, unused locale files (better than localepurge), logs, and cookies. Designed for Linux systems, it wipes clean 50 applications including Adobe Reader, Bash, Firefox, Flash, OpenOffice.org, Opera, Real Player, Skype, and more. It shreds files so that they cannot be recovered, and it wipes free disk space to hide insecurely deleted files. It offers both a simple PyGTK GUI and a command line interface for automation.
Final Config implements the preference dialogue (typically found under Edit->Preferences) as a separate application that can be used by another application (called the client application or client) through DBus. The available preferences and how they are to be presented to the user is described in an XML file (the desc file), which can be stored in a place convenient to the client. The client does not need to bother with the desc file; it just needs to pass along the file location when invoking the FinalConfig service.
GTK+ Recent Files Scrubber is a compact, lightweight Python script which uses GTK's RecentManager to watch for updates to all globally-available "Recently Used" lists (the ones which appear in Open dialogs and the like) and filter out anything in the folders you blacklist. Blacklist entries are hashed to make reading the blacklist not worth the effort.
QuickTile is a simple attempt to duplicate the basic functionality of WinSplit Revolution for users who don't like the Compiz Grid plugin. It should work on any X11 desktop with PyGTK 2.2+, a window manager that supports the modern range of NETWM hints, and (if you want internal keybinding) python-xlib.
The Procrastinator's Timeclock is a simple utility for people who suffer from excessive procrastination or distractibility. The utility achieves its benefits by allowing you to comfortably track just how much time your little "one more thing"s are adding up to and by helping to bolster willpower by providing a gentle distraction from temptations. Its design focuses on simplicity, intuitiveness, and a preference for keeping existing users rather than attracting new ones.