Mike Leavitt creates very quirky, sometimes a bit twisted, one off action figures. On his website he demonstrates the process he uses to create his sculptures. It's extremely interesting and I learned a bit about articulating figures which is something I've never tried, definitely worth checking out.
He also has a bunch of great demo videos up on his YouTube Channel
I should point out that he uses styrofoam for some of the internal structures, please do not try this most styrofoams release harmful chemicals when heated and may even catch fire in the oven (not all, I'm assuming he uses a safe variety but just to be safe avoid the stuff). Use a non-hazardous material like aluminum foil, dried paperclay, or oven safe self-hardening materials like magicsculpt and aves apoxie.