Markus Leonhardt has taken the shortest route possible to liquid cooling.
1. throw motherboard in fish tank
2. cover in vegetable oil
3. there is no step 3
Markus has been using this system for over a year. it is quiet and is cooled by the still functional fans circulating the oil. he has swapped components and even successfully used pulled hardware in other pcs.
This just boggles my mind. Wouldn't immersing your computer in vegetable oil short circuit it, or something like that? I also would have thought it would overload the fan motors. There are color pictures of the Oil Computer here, as well as more description, though most of it is in German. (via Reality Carnival)