cpuburn is is a set of programs that load x86 CPUs as heavily as possible for the purposes of system testing. FPU and ALU instructions are coded in an endless loop in an attempt to maximize heat production from the CPU, putting stress on the CPU itself, the cooling system, the motherboard (especially voltage regulators), and power supply. The tests may damage undercooled, overclocked, or otherwise weak systems and cause data loss or permanent damage to electronic components.
amforth is an extendible command interpreter for the Atmel AVR ATmega microcontroller family. It has a turnkey feature for embedded use as well. It does not depend on a host application. The command language is an almost compatible ANS94 forth with extensions. It needs less than 8KB code memory for the base system. It is written in assembly language and forth itself.
Powertweak-Linux is a tool to tune your system to its optimal performance settings. It started life as the replacement for the now obsolete kernel option 'tune PCI bridges', and has been extended to provide more features and support more chipsets. It can also tune network/filesystem performance using /proc/sys entries, disk elevator settings, and x86 CPU registers (needs 2.2.18 or 2.4.0test kernel), CDROM speeds, hdparm type features, and Sony VAIO backlight. It has both a GTK GUI and a text-based lister.
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.
Push Puppet Toy is a computer-controlled puppet that stands to attention when a friend joins an IRC channel or comes online on IM, and collapses when he leaves. The concept is very similar to the Availabot (http://availabot.com/), but works under Linux. Schematics, firmware for the puppet, and plugins for Gaim and XChat to control the puppet are provided.
cpuinfo consists of an API/library used by programs to get information about the underlying CPU. Such information includes CPU vendor, model name, cache hierarchy, and supported features (e.g. CMP, SMT, and SIMD). cpuinfo is also a standalone program to demonstrate the use of this API.
HeavenOS is an original, alternative 32-bit operating system for Intel 80386 compatible processors. It is made with NASM (The Netwide Assembler), and is not intended to compare to modern operating systems, but to try to get the best features and discover better ways to do things. It is intended to be a simple and pratical platform for development, running with a small amount of code.