asm5900 That's a PS2 MIPS assembler for the RISC5900 processor, running with Win32 Console.
It allows the programmer, to get full controll on output (except what a coder needs :)
PSXdeveloper Think of a very small clone of M$ Visual C Developer, usable to write introz and demos for the PS2. It should support projects, instruction highlighting, a good helpfile, automatic assembling and uploading and lots of more great stuff.
NEO Tutorial on programming NEO/MOD-Chips for PS2/PSX. It even shows you how to build a cheap PIC-Programmer.
NEO/MOD-Hexcodes available here.