Optical microscopes (the kind that you look through) are limited in how much they can magnify something by the size of light waves themselves, but a new trick that uses tiny glass spheres boosts magnification by a factor of 20, meaning that you can now watch a virus give you the flu in real-time.
Electron microscopes and atomic force microscopes have long been the standard for taking images of really really small things. The problem, though, is that you don't actually get to see what something looks like with an electron microscope. Instead, you get an image consisting of a bunch of excited electrons. Also, it's expensive, time consuming, requires special preparation of samples, and depending on how you do it, can be destructive to whatever you're trying to look at.
A team at the University of Manchester has figured out how to boost the resolution of a regular old optical microscope by twenty times, allowing them to see objects a mere 50 nanometers in size, way way smaller than the previous limit of only 0.001 millimeter. This level of magnification allows for the observation of things like viruses and and the insides of human cells, which is exciting because you can actually watch stuff happening in real time: you just put your eye up to the microscope, and there you go, no fancy detectors or computers or anything besides the Mk.I eyeball. There's a lot of potential here for figuring out exactly how viruses attack our bodies, something which hasn't been possible before.
All that was required to up the resolution was a sprinkling of glass microspheres, which act as light amplifiers of sorts. You just need a regular microscope to look through the microspheres at whatever you want to image, it's that simple. The microspheres are pretty cheap, too: you can buy about a million of them for $1.
While currently the smallest features that have been resolved using this technique are about 50 nanometers in size, the researchers say that "theoretically, there is no limit on how small an object we will be able to see." No limit, you say? Sounds good; I've been meaning to look in on my quarks for a while now.