The hunt is on for a new quantum state of matter called Supersolidity.
This state has never been conclusively observed but it would resemble another quantum state that has…superfluidity.
A superfluid is incredibly cool (barely above absolute zero in fact). It has zero viscosity which means it can actually climb up an out of a container. It can also flow through the tiniest pores of any container it’s in.
You may think that a supersolid would be super due to it’s incredible density but that’s not the case.
If you want more details. Checkout this article from my favorite science news-site Physorg.