RevenDream on. Only Liquid Nitrogen can cool the CPU enough to allow that sort of overclocking. I wrote a thread about some guys that did use Nitrogen to overclock to 6GHz.
I saw pics of the original 6GHz (P4) overclock. It was an open-air bench setup with a foot-tall tower over the CPU that somehow cycled LN2 to keep the damn thing cool. He had a video card and (I believe) one stick of RAM, no doubt 256MB--possibly only 128MB. I'd like to know what he was using to keep the northbridge cool. That's a bragging rights OC... totally worthless anyplace else. As for waterblocks, I have to recommend Dangerden.