Ok, you've read a lot about 3-D printing, from printing new prosthetic limbs to creating custom cufflinks. All great, exciting stuff, but so...large. No worries. Scientists at the Vienna University of Technology have shown that 3-D printing need not be consigned only to very big--or even slightly large--projects. They're using 3-D (or additive) printing technology to create realistic-looking sculptures that can be measured in hundreds of nanometers. As a reminder, a nanometer is one billionth of a meter. Blue light has a wavelength of about 475 nanometers. That's pretty small. How does it work? According to the scientists, "The 3D printer uses a liquid resin, which is hardened at precisely the correct spots by a focused laser beam. The focal point of the laser beam is guided through the resin by movable mirrors and leaves behind a polymerized line of solid polymer, just a few hundred nanometers wide. This high resolution enables the creation of intricately structured sculptures as tiny as a grain of sand." Their printer is also fast, the scientists say, able to print as much as five meters per second. That opens the doors to much bigger, and more practical, 3-D printed objects.