Imagine computers so small and powerful that all your district’s computing needs could be met with an array the size of a postage stamp. Imagine dozens of lightning-fast workstations on a grain of sand or tiny probes that cruise the bloodstream looking for trouble. These all would be possible with molecule-size computer components based on chemicals instead of chips and transistors, researchers said on July 16.

“What we are proposing is essentially building a computer in a test tube,” said Phil Kuekes, a computer architect for Hewlett-Packard in Palo Alto, Calif.

Such tiny, chemically assembled computer components could create devices billions of times faster and smaller than today’s personal computers—opening up a world of “Fantastic Voyage’-like possibilities.

Researchers at Hewlett-Packard and the University of California, Los Angeles, in a paper published in the journal Science, reported early success in the marriage of chemistry and computer technology.

They’ve found molecular switches that can be opened or closed—the first step in basic computing.

Currently, computers are run by semiconductor silicon chips that are increasingly jammed with transistors to make them faster and more powerful. Eventually, scientists say, it simply won’t be possible to push such chips any further.

That’s where “chemically assembled electronic nanocomputers,” or CAENs, come in. Scientists say such molecular-based computers will be much smaller, much more powerful, and a lot less expensive than silicon-based counterparts.

Researchers created their switch using two regular wires and synthetic rotaxane molecules. They were able to configure the switches into what are known as “logic gates,” the basis of computers.

“What we have here for the first time is a molecular device that is a real technology—not just an isolated device,” said James R. Heath, professor of chemistry at UCLA, who led the team. “This is a real step toward making a molecular computer.”

The next step is for scientists to put the molecules between much smaller wires and create a device that can perform basic computer functions. Substantial molecular electronics are still a decade away.

“We’re hoping to build something as complex as a chip you could have bought in the 1970s,” Kuekes said. “It will be very simple, but the point is it will have a real legitimate function, in a space much smaller than anyone can make a transistor now.”

That’s still about two years off, but researchers are already excited about the possible applications.

“Imagine millions of tiny computers everywhere in our lives. Tiny probes in the body, monitoring body functions—perhaps a very sophisticated pacemaker,’ said Eric Wong, a postdoctoral researcher from UCLA who is involved in the project.

“Eventually computers are going to be so small you won’t be aware of them. The computer won’t just be in your wristwatch, it will be in the fibers of your clothes,” Kuekes said.