With the Olympics due to kick off on 27 July in London, this article takes a look at how far science would be able to push human athletic abilities if all restrictions on doping were lifted. The article mentions anabolic steroids (up to 38% increase in strength), IGF-1 (4% increase in sprinting capacity), EPO/blood doping (34% increase in stamina), gene doping and various drugs and supplements, as well as more 'extreme' measures such as surgery and prosthesis. Hugh Herr, a biomechanical engineer at MIT, says performance-enhancing technologies will one day demand an Olympics all their own. But is that time already upon us?