Originally posted by: wisdomtooth
A long long time ago, Inwin used to sell a full ATX case called the A500 midtower, which has the PSU mounted vertically to the left of the CPU location. Because of that, the case is only 15.7" tall.
Problem with a PSU mounted in that orientation is that the heatsink for your CPU can't be very tall, and the case is a bit cramped.
Not sure where to buy that case these days since it has been long discontinued, but when I Googled it quite a few came up.
EDIT: A search on Newegg for "Mini Tower ATX" showed a lot of short cases with PSU orientation just like the InWin A500. Maybe that will work.
I agree that a horizontal desktop type case might be an option worth exploring.
HTH.