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.
Bokken is a GUI for the Pyew and Radare2 projects. It provides an interface to almost all the features of Pyew, and many in radare2. It's intended to be a multi-architecture disassembler and binary analysis tool, and maybe some day an alternative for commercial alternatives as IDA Pro. Currently, Bokken is neither a hexadecimal editor nor a full featured disassembler, so it should not be used for deep code analysis or for modifying files.
Darning is a tool for managing a series or sequence of patches to a software source tree, in the same vein as quilt but with extended functionality. It supports advanced patch concepts such as file mode changes and copying/renaming files. The GUI is the primary interface and the most complete, but a command line interface is also provided with fewer features at this stage.
Diffuse is a graphical tool for comparing and merging text files. It can work with many revision control systems as a diff viewer or merge tool. Diffuse is able to compare an arbitrary number of files side-by-side (n-way merge), and gives the user the ability to manually correct line matching and directly edit the files.