Joshua Klein will hack anything that moves -- his list includes "social systems, computer networks, institutions, consumer hardware and animal behavior." His latest project, though charmingly low-tech, has amazing implications for the human-animal interface.

Right now, Klein is working at Frog Design as a Principle Technologist, while developing mobile/social applications, health care-related systems and other tools that improve people's lives. He's the author of the novel Roo'd, which was the first modern book (after Tarzan) to be ported to the iPhone.