Humans may not use all of the brain’s computing capacity, but they do use most of the cranium for computing, according to biophysicist Bruno Michel at IBM’s Zurich research laboratory. Co-located cortices and capillaries keep our neurons powered and cooled with minimal fuss. Yet today’s computers dedicate around 60 percent of their volume to getting electricity in and heat out compared to perhaps 1 percent in a human brain, Michel estimates. Last week in Zurich, he told journalists about IBM’s long-term plan to help computers achieve human-like space- and energy efficiency. The tool: a kind of electronic blood.