These anonymous posters have been popping up around Los Angeles. It seems to be a new variant of "Obama is a terrorist" - or at least that he's very, very scary. But as Robert Dougherty points out, the messaging gets a bit muddled from there:
The Joker was many things, but was hardly a socialist. In fact, the Joker is the polar opposite of a socialist, and anyone who watched The Dark Knight would know that.
Socialism is the result of an all powerful central government that runs every aspect of life - but the Joker subscribes to anarchy, one of socialism's polar opposites. If the Joker was a socialist, he would be destroying Gotham in the name of an all powerful state. Instead, the self-described "agent of chaos" nearly brought down the state itself, and all of its most cherished institutions, so that nothing could bring order to Gotham.
Photos of the posters in action: