you know... i've thought about this quite a bit and really a cabinet is a cabinet. it will never be as functional, fresh, and easy to clean as a nice, professional made pvc cage in my opinion.
so i was at the local home store the other week buying trim... i think what i'm going to do whenever i go this route is to get black pvc cages and buy some nice trim/moulding/wood strips and basically trim out the cage, using liquid nails or something similar to affix the stuff to the face of the cage. a little paint or whatever to get everything matched up and it's done... for a fraction of the cost of a customer cabinet style cage (like cagesbydesign.com).