Processors: MIPS 64-bit RISC CPU (R4000 series) 93.75MHz and 64-bit MIPS Risc Co-processor
RAM: 4.5mb RAMBUS D-RAM 36M bit
Graphics Resolution: 256x224 to 640x480 + PAL 768x576
Colours: 21-bit colour video output, 32-bit RGPA
Sound: Digital Sound Wavetable Synthesis
Media Format: Cartridge
Control and Input Methods: 10 button analogue/digital controller with expansion slot
This was meant to be the Playstation killer, it never managed it but it posed the greatest threat thus far and built a loyal following. It was technically very impressive but Nintendo's insistence on holding onto the cartridge format was its downfall. Cartridges don't suffer from loading delays and can't be easily pirated but they cost a considerable amount more to produce than CD reducing the profit margin on every game sale. The real problem however was the limitations of storage size. 32mb on a large N64 cartridge just couldn't compete with 650mb on a CD.
1964 - My current favourite N64 emulator, highly compatible. Use with Rice's graphics plugin.
Archive 64 - One of the best resources on the Internet for Nintendo 64 reviews.
N64 Resource Page - A collector's site featuring lots of technical detail and pictures of the N64 and rare hardware.