The Open On-Chip Debugger
multi-platform cross assembler for 6502/6510/65816 cpu
Blazing fast and correct x86/x64 disassembler, assembler, decoder, etc
RetDec is a retargetable machine-code decompiler based on LLVM
A machine code manipulation library for Intel 64 and IA-32.
A low-power ISA design and simulator for a 2010 IEEE competition
A disassembler and a simulator for the MSP430 CPU
Emulator and assembler