I’ve been wanting to do this for a while, and now it’s finally done. Myself, and a few friends have finished building a computer completely submerged in mineral oil. Because mineral oil does not conduct electricity, computer components can be submerged in it without risk of shorting. It also helps to dissipate the heat created by the processor, and other chips. In our project, we use baby oil (mineral oil + fragrance). Visit the project page for this at ultimatecomputers.net for photos!