In Need of Villains

I have an idea for an Urban Fantasy, but I need an idea for the Big Baddies. I’m tired of demons, werewolves, and vampires. A goverment conspiracy run by a corrupt US senator who wants to sell arms to terrorists? Uh, no. That is so done.

What kind of villains would be original, badass, re-newable (can’t be just one dude, I need my heroes to plow through a lot of ’em), something interesting enough you’d like to read it?

Both sf (aliens, robots) and fantasy (demons, necromancers) type ideas welcome. What kind of villain hasn’t been done that would be supercool?