Richard Feynman arguably ranks pretty high when it comes to the Most Recognizable Physicists, surpassed only by Albert Einstein and (possibly) Stephen Hawking. He was brilliant, exuberant, colorful, and his interests extended beyond physics to art, theater, playing the bongos, strip clubs, and the remote country of Tuva. He's also one of the founding fathers of the field of nanotechnology.

Certainly he was among the earliest scientists to recognize the potential for exploiting the unusual physical effects that emerge at the nanoscale. He gave a famous lecture at Caltech in December 1959 called "There's Plenty of Room at the Bottom," about what might be achieved if scientists could manipulate and control things on a very small scale. (You can read the full text here.) At the time, scientists had succeeded in creating a device capable of writing the Lord's Prayer on the head of a pin. Feynman realized this was just the beginning, the first paltry baby steps to a technological revolution. He thought it would one day be possible to write the Encyclopedia Britannica on the head of a pin; all one had to do was reduce the size of the text 25,000 times.

In 1997 Freeman Dyson wrote that "New directions in science are launched by new tools much more often than by new concepts." He has a valid point. At the time Feynman gave his prophetic lecture, scientists lacked the necessary instruments and manufacturing techniques to accomplish such a feat, but Feynman was confident they would be developed. And scientists have indeed made enormous strides in the miniaturization game. Apart from the ingenuity of the science, I think Feynman would have been highly amused by the nanoscale "Bucky Badger" mascot created by Robert Hamers, a chemistry professor at the University of Wisconsin, Madison.

NanoBucky is made of tiny carbon nanofiber hairs, each measuring just 75 nm in diameter. I don't know how many fibers it takes to create a NanoBucky, but 9000 of the tiny mascots can fit on the head of a pin. Those nanofibers could be used to develop itty-bitty sensors capable of detecting chemical and biological agnts, or for energy storage in capacitors and lithium-ion batteries.

Why was Feynman so confident about his predictions? He realized that biology is teeming with examples of "writing" information on a very small scale. The human body contains billions of living cells, which store all the information eeded to coordinate all the functions of a complex organism. Cells are nature's nanomachines. That's why there's so much R&D devoted to engineering nanosystems that mimic nature's genius: we can create rudimentary nanoscale electronic devices, but they need to be much more robust and self-replicating if we are ever to realize their full potential.

That was the main point made by Michael Roukes, a professor of physics at Feynman's old stomping grounds, Caltech, who kicked off the Frontiers in Physics session with an overview of nanosystems of the future. "Nature's systems-nanotechnology still far outstrips what is engineerable today," he admitted, pointed to the profoundly robust and adaptive human immune system as an example. Our immune system provides what is essentially single-molecule sensitivity to invading pathogens: when pathogens are detected, information is conveyed by chemical "messengers," triggering an immune response to kill the interloper.

For Roukes, the living cell is a tiny integrated circuit/microprocessor, and single molecules can be viewed as living information "quanta." He'd like to exploit the cell's incredible sensitivity to detecting invading pathogens to create nanoscale biosensors (BioNEMS). The first step is being able to embed nanoscale biosensor arrays into microfluidic systems to form chip-based electronic "laboratories" for cell biology.

In his own way, Roukes is as much an optimist as Feynman when it comes to the inherent promise of cell-level nanosystems, particularly the potential for early disease detection, drug discovery and other basic research in medicine and biology that wold be possible if we had such a single-molecule sensor. "Ultimately, active nanobiotechnology will enable a detailed real-time window into the complexity of cellular processes," he said.