avrLab tries to be an complete IDE for the AVR microcontroller chips from Atmel. It offers an editor with syntax highlighting which has standard editor commands like copy, cut, paste, goto line, search, and replace. Additionally, it includes support for tavrasm (a compiler for the AVR assembly language), uisp (used for the communication to the AVR), and much more.
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.
asfpga is an assembler written for use in FPGA design. It can be easily modified for a particular instruction set. The ultimate goal of this software is to allow a FPGA designer to easily write assembly code for a custom instruction set. The current version allows you to create a listing file, a memory dump file which can be used in debugging HDL code using $readmemh() or equivalent routine, and a binary file which can be used to program an EPROM.
masmz80 is a very lightweight assembler for the Zilog Z80 processor. Objects generated contain information about global symbols, unreferenced symbols, and sections that need to be relocated, so it's easy to write code in many files and reference one project files' symbols from another. Linking these objects using included mlinkz80 produces an image ready for burning on an (E)EPROM.
The Quick C-- compiler is an experimental implementation of the C-- language. C-- is intended to be a "portable assembly language" that can be used as a target language by compiler writers. C-- features a simple C-like core and support for garbage collection and exception handling.