I'm building a wood case myself, using 2x2 pine for a frame and 1/4" birch plywood for the panels. Probably going to line it with some sort of sound dampening sheets, and definitely will have water cooling for the processor.
I thought about having my computer water cooled but right now my lake is frozen and it's to much work to chop a big enough hole to throw it [:I]in. Maybe in the spring if it keeps acting up