Once I found by accident an article by MacPherson: "Classical projective geometry and modular varieties", in "Algebraic analysis, geometry, and number theory" (Baltimore, MD, 1988), whose introduction thrilled me and I'm still curious about how that developed and if now a general theory of configurations as continuation of classical geometry exists. Do you know something about it?
copy from the article: "Classical projective geometry was a beautiful field in mathematics. It died, in our opinion, not because it ran out of theorems to prove, but because it lacked organizing principles by which to select theorems that were important. Also, it was isolated from the rest of mathematics. Much of what we do may be regarded as direct continuation of nineteenth century synthetic geometry. In fact, we hope the new motivation of studying C-complexes will provide projective geometry with one organizational principle, and with one relation tying it to "mainstream" mathematics. We note … representable matroids, arrangements of hyperplanes, and motivic cohomology. A large part of this paper's exposition is motivated by this dream of continuing classical projective geometry."
Edit: Mnev's theorem, that every scheme over Z "is" a moduli space for point-configurations in the plane, makes me ask about applications and if versions for other number rings exist?