I know, I know, Macaulay Culkin? Is he still around there? But listen to me, I don't know if he is still acting or even if he is remotely good but I'm just thinking that he looks a lot like the comic book version of the Joker. I'll let a couple of pictures and let the people that knows more about him decide.
I'm not saying that he's perfect but in a site where every casting choice is restricted to a few bunch Goslings, Fassbenders, Hamms, Coopers and Fillions different faces might be what we need.