TinyIB is a lightweight PHP image board which emulates the functionality of 4chan. If you use MySQL or SQLite, you can use it to create an efficient setup able to handle large amounts of traffic. If you don't use a database, it can store posts as text files for a portable setup capable of running on virtually any PHP host.
QMentat helps you practice mental arithmetic. It uses arbitrary-length fixed point arithmetic, and can handle any size numbers, only limited by the size of your screen (and in the case of division with an integer result, the speed at which the number can be factored). It is also quite configurable, allowing you to tailor the questions to your needs.
Sanewall is a firewall builder for Linux that uses an elegant language abstracted to just the right level. This makes it powerful and easy to use, audit, and understand. It allows you to create very readable configurations even for complex stateful firewalls. Sanewall can be used for almost any purpose, including control of any number of internal/external/virtual interfaces, control of any combination of routed traffic, setting up DMZ routers and servers, all kinds of NAT, providing strong protection (flooding, spoofing, etc.), transparent caches, source MAC verification, blacklists, and whitelists. Newer versions abstract the differences between IPv4 and IPv6, allowing you to define a common set of rules for both, while permitting specific rules for each as you need. Sanewall is a fork of FireHOL and can make use of existing FireHOL configurations.
Given a chord progression and a music style, JChordBox generates a song. It is a library tool that can generate backing tracks from a chord progression and a music style. It contains several command line processes detailed in the user guide. It also contains a MIDI song player that can loop, play, pause, stop, rewind, forward, mute, or solo tracks, display transport information, and much more. It runs in a terminal.
SCaVis is an environment for scientific computation, data analysis, and data visualization designed for scientists, engineers, and students. The program can be used for function and data plotting in 2D and 3D, histograms, statistical analysis, and symbolic calculations using the Matlab/Octave high-level interpreted language.
NumaTOP is an observation tool for runtime memory locality characterization and analysis of processes and threads running on a NUMA system. It helps the user characterize the NUMA behavior of processes and threads and identify where the NUMA-related performance bottlenecks reside. It uses Intel performance counter sampling technologies and associates the performance data with system runtime information to provide realtime analysis for production systems.