We've been asked for a few real pictures of our immersion cooling systems. While our rack mountable projects are still confidential and we can't publish any photos, have a look at the gallery in the Building Immersion-1 page. And while we do indeed use glass for small immersion cooling demo setups, rest assured that our finished immersion cooling tanks don't look anything like fish tanks (you don't want a couple of Kilowatts in a glass tank, trust me).
Here are two more pictures of some of the prototypes we've built last year. As you can see, immersion cooling can be very simple, especially considering that each of these tanks can hold what normally would go into a couple of noisy 19" server racks.