Think Google Street View, for browsing library stacks

Stack view takes Google Street View (where you can go down nearly every urban street for a look, virtually) but gives you a view of the library stacks.

You can't take a book off the shelf. What you can do is acquaint yourself with titles you may be interested in, books to enter into Google to learn more.

Stack view helps the serendipitious discoveries of browsing the physical shelves online. It's for when you're looking for something new; as they say

        searching is for when you know what you're looking for, browsing's for when you don't.”