True. There are very light 3.5" drives, as you and I know... and rather heavy ones. An equal 2.5" drive or something like is possible. I believe IBM's Deskstar hard drives used glass platters too, though I'm not sure for all the better. Anyway, what I was saying is that I usually don't see laptop drives that weigh more than 110 grams... good desktop drives weigh around 600 grams or more, IMO.