Here's a modified case for my LAMP development server. It's not exactly finished and it doesn't meet even modest safety standards, but it runs Linux and looks good doing it.
At first I put the computer in a leather satchel, which gave it a nice worn look, but had neither the layout nor the protection I need, especially since the poor machine also runs DJ software (Mixxx) at parties.
Step 1: The innards.
This isn't exactly going to be in step-by-step format since, well, frankly, you shouldn't follow what I did step-by-step.
I already had all the components stripped down and (except for the monitor) mounted to aluminum plate, so most of the work was simply arranging them appropriately in the case and attaching them with a lot of rivets and a little double-stick tape. This was slightly complicated, since the wireless card has to dodge the support for the monitor when the case is closed.
Note the unshrouded power supply, which I certainly wouldn't recommend copying âit's just what I had on hand. I have no idea whether the aluminum foil lining the case (attached with spray glue) actually provides any degree of shielding (at least it's grounded), but it felt better to attach the parts to it than to the bare hardboard.