Zero Install is a decentralised cross-distribution software installation system. Other features include full support for shared libraries (with a SAT solver for dependency resolution), sharing between users, and integration with native platform package managers. It supports both binary and source packages, and works on Linux, OS X, Unix and Windows systems. It is fully Open Source.

A port of BSD2.11 to a MIPS-based microcontroller with 128 kiB RAM.

MXE (M cross environment) is a Makefile that compiles a cross compiler and cross compiles many free libraries such as SDL and Qt. Thus, it provides a nice cross compiling environment for various target platforms (including Windows).

This is a distribution package of ancient UNIX 7th Edition together with a PDP-11 simulator and instructions how to get things running.

New (started in 2012 TBC) open source (GPL) editor supporting Clojure, ClojureScript, Javascript, Python, HTML, and CSS. More languages can be added via plugins in the future. LightTable is written in ClojureScript and runs on Windows, OS X and Linux.

Program to query and set the status of the keyboard LEDs on Mac computers.

The RADclock project (formerly known under 'TSCclock') aims to provide a new system for network timing within two years. We are developing replacements for NTP clients and servers based on new principles, in particular the need to distinguish between difference clocks and absolute clocks. The term RADclock, 'Robust Absolute and Difference Clock', stems from this. The RADclock difference clock, for example, can measure RTTs to under a microsecond, even if connectively to the time server is lost for over a week!
The RADclock is available and can be used as an alternative to the ntpd daemon to provide convenient system clock synchronisation for systems running FreeBSD and Linux. In terms of local hardware, it exploits the availability of counters such as the HPET counter or the TSC (Time-Stamp-Counter) commonly found in PC architectures.

The sigrok project aims at creating a portable, cross-platform, Free/Libre/Open-Source signal analysis software suite that supports various device types (e.g. logic analyzers, oscilloscopes, and many more).

It is licensed under the terms of the GNU GPL, version 3 or later.

A tool for editing version-control repository history reposurgeon enables risky operations that version-control systems don't want to let you do, such as editing past comments and metadata and removing commits. It works with any version control system that can export and import git fast-import streams, including git, hg, bzr, CVS, and RCS. It can also read Subversion dump files directly and can thus be used to script production of very high-quality conversions from Subversion to any supported DVCS.

Manual of the GnuTLS (transport layer security) library, which appears to provide a good overview of TLS/SSL.