PCMech live chatter shadowpr tossed me a link when I was talking about submersible PCs and Macquariums. The link he provided shows an entire computer submersed in a light mineral oil that actually looks really decent. After the video are links you can follow for more information.

iMacquarium: http://imacquarium.cool-mac.com/aquaria.html

Submersible PC (with additional video): http://www.pugetsystems.com/submerged.php