Of course, to make any use of this feature, you need a pair of red/cyan anaglyph glasses – those iconic cardboard glasses for viewing in 3D.  But the point is that it’s cool and fun – and isn’t that what reading is all about?

To view a book in 3D on Google Books, add &edge=3d to the book’s URL (Note: be sure to add this parameter before the # in the URL).  (Honestly, they had it right when they first released this feature with a link to the 3D version.  But I guess they figured anyone geeky enough to use it, was also geeky enough to figure out how to add a query string parameter to a URL.)