The  Italian geeks at PCTuner.net have done what seems almost impossible - overclock a Pentium 4 CPU to double it's rated CPU speed to 7Ghz  or 7104 Mhz to be more precise.  The overclocking technique uses a precisely controlled liquid nitrogen cooling system with a custom container block  and beats pretty much all other overclocking records we know. Head over to PCTuner.net for more details.