I was looking for a suitable metal case for the uBITX and ended up wandering down the mailboxes section of the local Lowes. They had a slim upright letterbox, the Gibraltar City Classic, for under $13.
The letterbox has a recessed back panel that limits the interior thickness to 2.5", but all you have to do is pop the panel it off and turn it around, and you get the full 3" of space. I added some rubber feet and used some scrap metal to hold the jacks and knobs on the same side as the board. The front lid neatly flips open to reveal the goods.
These cases are in bronze and black, without any US MAIL detail on them---there is a snap-on plastic fleur-de-lis if you want it, but beyond that it's just a case.
Now I can tell people that I got my uBITX in the mail, wah wah wahhhhh....
Thanks, Xcott K2CAJ