Hello Mike .. I have just finished to convert an iMac 233mhz into a "supercube" since I am broke and I really want a cube I had to make myself one ;-)
I attached some photos (see below) to give you an idea of the finished product. Notice the original speakers mounted inside the case and also the original handle is mounted on top of the case.

The case is 10x10" and made out of clear acrilic I could have made it a bit smaller but it's really tight in there.. I kept the original power supply , the handle and speakers.

The PS is mounted on the right side so that the power plug is in the back of the "cube"

The motherboard is mounted on the bottom side and lifted about 2-3" using some spacers there is also a air vent below the MB, right on top of it I mounted a fan with green led (ebay for $3.75) the ports are now at the left side of the case that makes it easy to access it I also kept the original video /ir assembly board which is mounted on the rear.

Rather than mounting the original HD and CD rom in the front (I wanted a clear view of it's guts) I opted for the top just like a real cube :-)
I wish this was a slot loading cd rom , the tray is a bit awkward but it works well

tools I used:
a dremel with cutter attachment, screwdriver and a drill for drilling the various holes and some crazy glue

It took me a weekend to put it togheter and if you look closely you can tell :-)
Thank you
-Luca Fornari

Photos:

Other iMac/System/Case Conversion Articles: See the Systems page.