TINY is a small Linux distribution designed especially for reusing old computers. It has very low demands in terms of hardware capacity, and even a Linux beginner can install it easily. No CD driver is required for installation, even for standalone machines. TINY is GUI capable . As long as your machine can bear it, you can run all available Linux applications on it.
TrinityOS is a step-by-step, example-driven HOWTO on building a very functional Linux box with strong security in mind. TrinityOS is well known for its strong packet firewall ruleset, Chrooted and Split DNS (v9 and v8), secured Sendmail (8.x), Linux PPTP, Serial consoles and Reverse TELNET, DHCPd, SSHd, UPSes, system performance tuning, the automated TrinityOS-Security implementation scripts, and much more.
TuxTyping is an educational typing tutorial game starring Tux, the Linux Penguin. The player guides Tux to eat fish which are falling from the top of the screen. Each fish has a letter or a word written on it. Another mode of gameplay is to stop comets from destroying cities. There is also a mode for players to learn the correct finger positions.
The VP7 Way Kool Project is a GTK application which simulates a laboratory experiment with radioactive nuclei. The user can choose between many predefined radioactive sources or create new ones. The number of decayed nuclei and the activity of the source can be determined with a built-in counter. The beam can be attenuated with shields of paper, aluminium, and/or lead.
Weka is a collection of machine learning algorithms for solving real-world data mining problems. It is written in Java and runs on almost any platform. The algorithms can either be applied directly to a dataset or called from your own Java code. Weka is also well-suited for developing new machine learning schemes. The development version contains a GUI with visualization tools and direct database access.
WIMS (WWW Interactive Mathematics Server) is a CGI Web application designed to host interactive mathematical educational activities such as exercises, computational math, and graphing tools. It features automatic score processing with strong anti-cheating mechanisms, virtual classes allowing teachers to guide/control student works, online exercise creation, animated graphics, a message board allowing inline mathematical formulas, and more. It can also be easily used for education within other disciplines.