Thank you kindly for your offer on the system design.

I'm planning on using an ordinary cabinet, in which I'll have steel plate "trays" acting as bases for the components, double layered, a bit like this design model:
http://www.calvin.edu/~adams/research/microwulf/design/

I have the cabinet ready to be modified and for the cooling I have a 1200 m3/h extractor fan, which will suck the hot air from the cabinet and vent it out of the apartment. In addition I'm playing with the idea of using an arduino controlled thermostat to control and use the excess heat for the heating of the apartment (with the winters in Finland being kind of chilly...), but that's just an extra idea when I eventually finish the rack cabinet itself.

There are still some design issues to be tackled, primarily with the tray design. I want them to be height adjustable to accommodate as much hardware as possible in the limited space, as well as allow the maximum possible airflow to control the heat...
But all in just time, I'll get it done and maybe post some pictures of the final product!

Out of curiosity, what kind of system are you running yourself? You seem to be putting out pretty impressive numbers in OGR alone!
...And also out of curiosity, how much DO you generally pay for electricity in the US? I honestly have no idea...

-S