Grant mentions purchasing a Marathon Deskmount for his G4. I downloaded the Deskmount installation instructions (PDF), and had a good chuckle. These guys have a great sense of humor, and this has to be the funniest product manual I've read in a while. Give it a read, it's only 8 pages and 2 of those are the cover and the legalese. We had a similar product in use in our graphics lab, but it's not nearly as elegant as the Marathon Deskmount, though it doesn't require modification to the G3/G4 case. I decided that I bang my knees into the G4s we do have mounted this way too much for my liking.