A recent discussion on the Mac couch:

Snookums: haha. It would be a bit hard on your arse
Me: Somebody commented that it would look sweet with Happy/Sad pillows like the Mac startup screen.
Snookums: now, if they were all up and running it might be better — then it would be warm and have a pleasant vibrating effect

Looks like this idea occurred to John too. Great minds think alike.