Here's my (pretty much finished) custom mini-itx computer case.
I was going for the smallest case I could build with just an epia board, regular 3.5" hard drive, and a microATX psu as the computer components. I also wanted to take advantage of the PCI slot someday which is one reason for the orientation of the parts. The only "not nice" method of mounting something to the aluminum frame was the PSU due to the strange placement of holes and my not wanting to drill holes in the PSU. In order to have adequate airflow circulating through the case, I had to flip the PSU so the fan was facing the motherboard. Turns out of I run the case the normal orientation (turned so blue 80mm on top), the PSU gets a bit hot with little pockets of air getting stuck inside.
Now I run the case as shown in the picture (blue 80mm on the side). Approximate dimensions for the case are 8.5" x 7.75" x 6". There still is no "back panel" plexi that covers the back of the case. I think I might have all the necessesary tools to make one the only problem is being accurate and figuring out what I'm going to do about the PCI card. So for now, I wanted to finish the thing and have it run so no back panel yet.
You might be wondering what someone would do with a computer that has no cdrom and is incredibly slow. Well I have a perfect idea: simple file server.