In <a href="https://mathoverflow.net/questions/14739/how-can-i-define-the-product-of-two-ideals-categorically">question #14739</a>, I asked whether the product of two ideals of a commutative ring $R$ could be defined lattice-theoretically the same way the sum and intersection can.  Bjorn Poonen gave a great counterexample that shows the answer is no!  This supports a point fpqc had been trying to make to me earlier that the relationship between $R$ and the Zariski topology on $\text{Spec } R$ was more subtle than I had thought: in particular, it has more structure than just the Galois connection.