Whilst surfing the net for an idea of what my new machine will be like when I have to shell out for PCI Express, 64-bit etc just to play Doom III (probably ;) ), I found this lovely article on a great case.
This case rocks. Its compatible with ATX and BTX motherboards apparently and supports what looks like quite a mean number of hard drives.
Although I guess I will wind up getting something that is completely BTX, this did give me an idea of what I would want my BTX system to sit in.
More here.