eCos (Embedded Configurable OS) is an open source, configurable, portable, and royalty-free embedded Real Time Operating System. It is written in C++, provides all the usual OS things. You configure the OS so that the parts you don't need aren't loaded to the embedded system. eCos is released under a modified GPL that allows for its use in embedded systems without having to GPL the embedded application.
DirectFB is a thin library that provides developers with hardware graphics acceleration, input device handling and abstraction, an integrated windowing system with support for translucent windows and multiple display layers on top of the Linux framebuffer device. It is a complete hardware abstraction layer with software fallbacks for every graphics operation that is not supported by the underlying hardware.
Ewrt is a Linux distribution for the Linksys WRT54G that was forked from the Linksys and Sveasoft code bases. It is designed to meet the needs of open wireless network operators by providing a captive portal based on NoCatSplash and large-scale management functionality on a stable and low-cost platform.
NASLite is a Network Attached Storage (NAS) server operating system designed to transform a basic computer into a dedicated file server. Utilizing highly optimized versions of Samba, uCLibc, BusyBox, and various other Linux tools, it provides SMB/CIFS, FTP, or NFS filesystem support. It accommodates multiple client OSes: Windows, Mac OS X, and Linux. NASLite offers SMART disk monitoring and large file support, and is incredibly easy to install and administer.
SimMon is a cross platform monitoring tool which runs on almost any OS that supports the Java Virtual Machine 1.4+. Monitoring is done through the execution of existing monitoring scripts (Perl/VBS) or existing shell commands. Currently monitoring scripts are available for Solaris, Linux, Mac OS X, and Windows based systems. Network devices can be monitored via the integrated SNMPv1 scheduler.
Agnix is a small, educational operating system kernel for i386, supporting 32-bit protected memory mode, paging, hardware switched tasks, memory tests, PCI bus, devices, PCI IRQ routing, RT timers, network protocols. It is available with all the source code and is fully compatible with the Linux kernel API.
Dconf is a tool to collect a system's hardware and software configuration. It allows you to take your system configuration with you and compare systems (like nodes in a cluster) to troubleshoot hardware or software problems. It can also be configured to send out configuration changes at given intervals to a group of people, or store a new snapshot when system changes happen.