I'm currently modding my *generic* case with a side window (real glass!).
I cut a 10"X10" square into the side of the case, and had Lowe's cut me a 12"X12" piece of glass. I then attached the glass to the inside of the case using Silicone. Then I purchased some galvanized steel wire mesh and am currently attaching that behind the glass. Then I am going to install my ZALMAN CNPS7000B-CU with blue led lights and some Antec blue led case fans. Along with it two Cold cathode UV lights and special UV IDE cables.
I'll post pics when I'm done.
I tried using plexiglass but it scratches way too easily, so I'm sticking with glass.