What a great idea, Amy.  In the past, I used the same approach to change the height of a desk, depending on what I was working on.  It wasn't to allow standing, just to allow the work to get closer to my eyes, so I could remove my glasses and not have to bend over to get close to the work.  I'm more than a little near-sighted, as you may have guessed :).  That was before I gained a few decades and needed lenses to help with close vision.  The more I think about it, however, I may revive the arrangement.  I wouldn't need a coffee table either, just a wooden box of appropriate height.......