I am going to go with Alan Greenspan. Prevented the regulation of derivatives, and fueled the housing bubble with the Fed's low interest rates.

I agree. Greenspan forgot, or perhaps ignored, the dictum of one of his predecessors, William McChesney Martin, who said that the job of the central banker is to take away the punch bowl just as the party is getting going!

Hey how come the auto sector CEOs agree to sell their jets and take $1 a year salaries for loans but no one is asking that from a finanacial sector recieving $Trillons$ in government loans/aid (vs. the big 3's $25 billion) who also happened to have caused this crisis?