Flat Assembler is a fast and efficient self-assembling 80x86 assembler. It supports x86 and x86-64 instruction sets with MMX, 3DNow!, SSE up to SSE4, AVX, AVX2, and XOP extensions. It can produce output in binary, MZ, PE, COFF, or ELF format. It includes powerful but easy-to-use macroinstruction support and does multiple passes to optimize the instruction codes for size. It is written entirely in assembly language.
Fenris is a multipurpose tracer, debugger, and code analysis tool that detects and documents high-level language constructions, can recover symbols, graph program execution flow, detect internal functions, recover symbol tables, and deal with anti-debugging protection. It features a command-line interface as well as a SoftICE-alike GUI and Web frontend.
Libecc is a C++ elliptic curve cryptography library that supports fixed-size keys for maximum speed. The goal of this project is to become the first free Open Source library providing the means to generate safe elliptic curves, and to provide an important source of information for anyone with general interest in ECC.
PopAsm is an assembler (an assembly language compiler) designed to support the syntaxes of TASM/MASM and NASM, gathering together the best features of each of them. It is intended that it will support all instructions from Intel compatible CPUs, including MMX, 3DNow!, and SSE extensions.
Shilosh OS provides a secure and stable operating system based on a highly modified Linux kernel, with its own package system similar to BSD's "ports", BSD Init scripts. Compatible with x86 and Power PC, it is also 99% compatible with Windows 9x. It is easy to use and includes complete documentation in many languages.