[MsgrMartinez]

In Search of Schrodenger's Cat - An accessible book about quantum physics. Even if you're not interested in science per se, you should be interested in what modern science has to say about the nature of reality.

Sophie's World - A primer of the history of Western philosophy, told in the context of a frame story (so it is not at all dry).

Neither of these are "great works" but can and should be read by anyone who is intellectually curious about the world around us.