People will occasionally include Mad Hatter amongst some of Batman's greatest enemies, but those people are almost sweetly naive and misguided.
He's like the Mad Hatter from Alice In Wonderland, except he's a child molester. What fun.
Tom Baker is the Comics Editor at WhatCulture! He's heard all the Doctor Who jokes, but not many about Randall and Hopkirk. He also blogs at http://communibearsilostate.wordpress.com/