I thought this was pretty cool. They got one of the upcoming AMD FX-series processors (8 cores), disabled 6 cores then overclocked it to 8.429ghz with liquid helium for cooling. I'm hoping the retail chips overclock well on air when they're finally released, there's some reports of >4.5ghz on cooling that costs <$100 but they might not be true. If it is, then it's my next upgrade. Of course, high frequency doesn't necessarily mean high performance... and it has yet to be seen how fast it actually is.

http://www.youtube.com/watch?v=UKN4VMOenNM&feature=player_embedded