Security specialists of the Computer Security Group ( http://www.cs.ucsb.edu/~seclab/ )at the Department of Computer Science of the University of California, Santa Barbara have published an article, how they could take over the Torpig Botnet for few days.
http://www.cs.ucsb.edu/~seclab/projects/torpig/index.html
http://www.cs.ucsb.edu/~seclab/projects/torpig/torpig.pdf