Researchers from the University of Florida have developed a new bioprinting process that allows them to print soft, microscopic shapes from things like human cells or tiny electronics. The secret is a granular hydrogel that has properties of both a liquid and a solid. The material allows the printing head to easily move through it like a liquid while depositing the printing medium, however it completely holds its shape and prevents the inks from diluting or dispersing as if it were solid. Researchers created microscopic Russian nesting dolls, a tube tied in a knot and even replicas of small jellyfish. You can read more about the process over on 3DPrint.com: http://3dprint.com/97978/3d-printing-microscopic-cells/