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The microscopic world is truly one straaaaange place:

Australian researchers have experimentally shown that microscopic systems (a nano-machine) may spontaneously become more orderly for short periods of time--a development that would be tantamount to violating the second law of thermodynamics, if it happened in a larger system. Don't worry, nature still rigorously enforces the venerable second law in macroscopic systems, but engineers will want to keep limits to the second law in mind when designing nanoscale machines. The new experiment also potentially has important ramifications for an understanding of the mechanics of life on the scale of microbes and cells.
There are numerous ways to summarize the second law of thermodynamics. One of the simplest is to note that it's impossible simply to extract the heat energy from some reservoir and use it to do work. Otherwise, machines could run on the energy in a glass of water, for example, by extracting heat and leaving behind a lump of ice. If this were possible, refrigerators and freezers could create electrical power rather that consuming it. The second law typically concerns collections of many trillions of particles--such as the molecules in an iron rod, or a cup of tea, or a helium balloon--and it works well because it is essentially a statistical statement about the collective behavior of countless particles we could never hope to track individually. In systems of only a few particles, the statistics are grainier, and circumstances may arise that would be highly improbable in large systems. Therefore, the second law of thermodynamics is not generally applied to small collections of particles.

There's another article from a couple years ago that I can't find right now, where scientists were able to structure the physical environment surrounding a molecule or some kind of nanoparticle such that the random Brownian motion was channeled into a specific direction, like a ratchet. The idea there was, again, that the 2nd Law of Thermodynamics doesn't apply as forcefully to a very small object as it does to something on a macro-scale, and so nanoengineers can have a very different set of constraints to work with than engineers who build things on "our" scale.

You think thats weird, look at what my quantum mechanics professor recently did. A computer that runs when its off, well sorta, its on and off a the same time.

CHAMPAIGN, Ill. — By combining quantum computation and quantum interrogation, scientists at the University of Illinois at Urbana-Champaign have found an exotic way of determining an answer to an algorithm – without ever running the algorithm.

Using an optical-based quantum computer, a research team led by physicist Paul Kwiat has presented the first demonstration of “counterfactual computation,” inferring information about an answer, even though the computer did not run. The researchers report their work in the Feb. 23 issue of the journal Nature.

Quantum computers have the potential for solving certain types of problems much faster than classical computers. Speed and efficiency are gained because quantum bits can be placed in superpositions of one and zero, as opposed to classical bits, which are either one or zero. Moreover, the logic behind the coherent nature of quantum information processing often deviates from intuitive reasoning, leading to some surprising effects.

“It seems absolutely bizarre that counterfactual computation – using information that is counter to what must have actually happened – could find an answer without running the entire quantum computer,” said Kwiat, a John Bardeen Professor of Electrical and Computer Engineering and Physics at Illinois. ”But the nature of quantum interrogation makes this amazing feat possible.”

Sometimes called interaction-free measurement, quantum interrogation is a technique that makes use of wave-particle duality (in this case, of photons) to search a region of space without actually entering that region of space.

Utilizing two coupled optical interferometers, nested within a third, Kwiat’s team succeeded in counterfactually searching a four-element database using Grover’s quantum search algorithm.

“By placing our photon in a quantum superposition of running and not running the search algorithm, we obtained information about the answer even when the photon did not run the search algorithm,” said graduate student Onur Hosten, lead author of the Nature paper. “We also showed theoretically how to obtain the answer without ever running the algorithm, by using a ‘chained Zeno’ effect.”

Through clever use of beam splitters and both constructive and destructive interference, the researchers can put each photon in a superposition of taking two paths. Although a photon can occupy multiple places simultaneously, it can only make an actual appearance at one location. Its presence defines its path, and that can, in a very strange way, negate the need for the search algorithm to run.

“In a sense, it is the possibility that the algorithm could run which prevents the algorithm from running,” Kwiat said. “That is at the heart of quantum interrogation schemes, and to my mind, quantum mechanics doesn’t get any more mysterious than this.”

While the researchers’ optical quantum computer cannot be scaled up, using these kinds of interrogation techniques may make it possible to reduce errors in quantum computing, Kwiat said. “Anything you can do to reduce the errors will make it more likely that eventually you’ll get a large-scale quantum computer.”

In addition to Kwiat and Hosten, co-authors of the Nature paper are graduate students Julio Barreiro, Nicholas Peters and Matthew Rakher (now at the University of California at Santa Barbara). The work was funded by the Disruptive Technologies Office and the National Science Foundation.