Entomologist is a desktop client for working with various bug trackers. Currently Bugzilla, Mantis, Trac, and Launchpad are supported, with more under development.
glogg is a multi-platform GUI application to browse and search through long or complex log files. It is designed with programmers and system administrators in mind. glogg can be seen as a graphical, interactive combination of grep and less.
An Incan Abacus emulator.
A chess interface for KDE.