NASM is a very good assembler for all projects. It is very simple and straightforward and doesn't do any of the ASSUME crapola. All memory references are in brackets and ...well to find out more google it and visit it's site. It has been moved to sourceforge.net I believe, but ever since it's inception it has not left my drive. A very good free assembler that kicks MASM and TASM to the curb. There is another one called FASM I've heard good things about, but I have no experience with it.