Citizens of the digital age seem to have grown accustomed to the fact that technological progress is synonymous with shrinking. Computers no longer take up entire rooms, and their speed only increases each year as more switches and chips are jammed into RAM and processors. Mobile phones no longer come in briefcases, although it does seem they have recently stalled at a size just too big to comfortably fit in my front pocket. But the difference between the thinnest cellphone available and the true cutting edge of small technology is akin to comparing the size of Mount Everest to an anthill. The field in question is nanotechnology, and it has the potential to effect countless aspects of our lives.

Nanotechnology exists at the nanometer scale, or to those that don't have their metrics down, one-billionth the size of a meter. At this level, the direct building blocks of the materials produced are atoms themselves. Nanotubes, for instance, are long cylinders made up of the molecule fullerne, a hexagonal matrix of carbon atoms first described by famed chemist Buckminster Fuller. Great, you're saying, so they're really small. Big whup! But if I happened to mention that these tubes could be woven into a transparent sheet of material, stronger than steel, conductive to electricity and 1000 times thinner than a human hair, maybe your attention might pick up a bit.

Scientists working as part of the Nanotech Institute at the University of Texas in Dallas have recently made these nanosheets a reality, as well as commercially feasible. This group already made a splash with their creation of nanofiber, a string-like material made from a mixture of nanotubes and polyvinyl chloride, which defeated spider silk to become the strongest material on earth. Able to withstand a tensile force of 600 joules/ gram, the material is 20 times stronger than Kevlar, the protective material in bulletproof vests.

Nanosheets are not a new idea, but the leap of the Dallas scientists comes in the method of their creation. Previously, these extremely thin sheets were constructed according to the principles of papermaking, one of the oldest human technologies. This process proved to be extremely slow due to the penchant of the nanotubes to form a sludge that was difficult to work with. In the new technique, the interactions between a "bamboo forest" of vertically aligned nanotubes cause them to fall into a sheet when they are pulled apart. By forming the material in this way, the researchers were able to produce 5 cm wide sheets at a rate of 7 meters per minute, not too shabby in comparison the 20 meter per minute rate of wool spinning. If such nanosheets begin to be produced commercially, they could lead to products such as flexible computer screens, new solar cells and super-light, extra-durable materials.

Moving on in our nanotour, we rest at a bespectacled youngster on a soccer pitch, about to miss a breakaway goal due to his fogged glasses. Fogged glass is the bane of astigmatic athletes, post-shower shavers, and humid weather drivers the world over. The smart scientists at MIT never cease to search for solutions to the problems of the world, and its seems they have come up with an antidote to this one as well. By coating glass in a 7 nanometer layer of polymer fibers and nanoparticles, they have been able to eliminate the phenomenon of fogged glass. The particle layer acts as a "molecular diaper" soaking up the individual water droplets that form fog and spreading them into a thin water layer that doesn't occlude the visibility.

Like the nanosheets, this process already seems to be commercially viable. The research team showed the ease of the process by enlisting local high school students to help out. The procedure is pretty much "Betty Crocker," as we like to say in lab speak, and involves dipping the glass in a few different solutions, and then baking it at 500 degrees for a few hours. This heating step currently limits the materials that can undergo the process, making plastics out of the question since they would melt. The MIT team has already been approached by a number of car companies seeking to use the technology to make a better windshield. Unconfirmed reports indicate that Toyota was one of the first car companies to express interest, hopefully to remediate the infamous "Toyota-Fog" problem in nearly every car the manufacturer produces.

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