Ya know... you could be the one to right a "Hot Fuzz" xover with HP. After all, the villains in Hot Fuzz chant "The Greater Good" and if Harry happened to be in retirement a few years after beating Voldie and sees men in black cloaks terrorizing the town of Wells... well, he might be a bit peeved. And it would cross over nicely. And be funny. "Crusty jugglers!"