Gaiman .. fanfic? Let's see, there's the one where Dumbledore meets the Marquis, the one where Door and Richard go visit the angel Heurtebise in Paris, the one with giant rats and Baltimore Below

... all my Gaiman ideas these days are Neverwhere based. And I don't even have a copy of Neverwhere.

(The urban fantasy, I fear, would end up closer to LKH than gNeil. Although I could hope...)