I've been trying to post this for a couple days now, but the site got hammered from all the attention. What's so cool that the internet, collectively, stomped their poor servers? Simply, the coolest Xbox 360 mod to date!
The creator was looking for a way to quiet his 360 down. It wasn't that it was excessively loud or unstable, it was more for the thrill of the hunt (and because he's "easily irritated"). He takes us step by step through the process, from taking the case apart, removing the heatsinks, making the water block, assembly, everything. Without any fans, the finished product runs much quieter... but still not quiet enough: "The only thing I may need to change is the voltage of the... pump, at 12V I can hear a faint hum when its running. I may reduce it to 9V in the future."
Wow, he is easily irritated.