My proposal is an Apollo Lunar Module from the Apollo 11 mission to commemorate the 40th Anniversary of the first men on the moon.
It would be a challenge to make it look good and have it big enough to support all of the PC components but it would be a very unique case to see.
I believe that there are enough flat surfaces for the necessary ports to be placed and possibly hidden under panels. Water cooling could be a solution if fans would not be adequate enough and the docking port on top of the lander could be used as a fill port.
If the lander's legs could not be made to support the weight of the PC then a clear support could be placed under it to help disperse the weight. If possible it might be great to have a stand underneath the case that looks like the lunar surface.
Thank you for your consideration and hopefully this can come to fruition.
This is a lander that was never used and is now on display at the National Air and Space museum.
This is the back of the Apollo 11 lander while on the moon.