On a sidenote, I was rather surprised with the workbench in that photo. I put a PC on it to test something and the whole thing vibrated like a drum. I didn't really worry about sound when I built it because it's not for "noisey" stuff, but I didn't expect it to amplify the vibration and it felt like it transmitted it straight into the structure.

Lots of experimenting to be done with isolating and dampening, I think.