Whether potholes are formed by the impacts of space rocks or by the drug-induced rampages of some new species of mutant moles may still be up for debate, but in either case, nobody likes them. Now, some plucky undergrads have come up with a way to fix potholes with a weird sort of non-Newtonian goo, because goo is good for fixing everything.
Newtonian fluids are fluids that act like fluids. Non-Newtonian fluids are fluids that act like fluids only sometimes. Most commonly, the times that non-Newtonian fluids don't act like fluids is when they're subjected to stress, like if you punch them or run them over with a car. The easiest way to experience this for yourself (and you may have done it in science class) is to mix corn starch and water: you'll get a gooey substance that you can pour like a liquid, but when subjected to a shock it instantly firms up as all the individual little particles of corn starch jam together into a solid.
This slightly bizarre property has recently been harnessed for things like liquid body armor that only turns hard for the millisecond when you're actually being shot, but society has a whole might get more use out of pouring the stuff into potholes. Here's how it works: a bunch of something like corn starch gets poured into a Kevlar bag that can be carried around with you, and if you run into a pothole, just put the bag in, fill it with water to mix up the non-newtonian fluid, seal it up, and you're done. Since you're filling the pothole with a liquid in a bag you're guaranteed an instant perfect fit, and whenever a car runs over the thing, it snaps into a solid and the pothole vanishes.
The fluid in the bag, while clever, is sadly not intended to be a permanent fix. The concept comes from undergraduates at Case Western Reserve University in Cleveland, who designed it to last for a couple weeks until a more permanent pothole fix can be implemented. On the upside, the Kevlar bags (which are the expensive part) are reusable, making the whole idea a very cost effective (albeit temporary) way to take care of spontaneous road cratering.