Re: Nice story, bro.
I used to be paid to work on them. Today, I restore them because somebody has to. The read/write assembly weighs quite a bit, yes. The actual moving mass, however, not so much.
Yes, you can make the drives walk. On well waxed floors. It is very hard on the equipment, though ... regardless, there is no way to fling the platters across the room, alas.
 Or I'm a glutton for punishment ...