Instructables has a detailed set of how to's to let you convert your computer case into a taxidermy beaver. Nothing says quality technology like dead animals. It's pretty easy, just look at step one:
Purchase a beaver of your very own
There are lots of old taxidermy mounts out there - garage sales, antique stores, ebay are all good sources for older pieces. You'll probably want a high quality mount since you'll be removing the bulk of the internal structure, so better quality (ie not falling apart) probably means stronger.