Autonomic Restoration of Electrical Conductivity

Self-healing of an electrical circuit is demonstrated with nearly full recovery of conductance less than one millisecond after damage. Crack damage breaks a conductive pathway in a multilayer device, interrupting electron transport and simultaneously rupturing adjacent microcapsules containing gallium–indium liquid metal (top). The released liquid metal flows to the area of damage, restoring the conductive pathway (bottom).

Autonomic Restoration of Electrical Conductivity Blaiszik 2011 Advanced Materials Wiley Online Library

Self-Healing Polymer 'Terminator Polymer'

This is a neat trick. After slicing a tube of gelatinous material in half with a razor, researchers stick the two pieces back together again. After they've sat together for two hours at room temperature, the pieces are impossible to pull apart. The material, a new invention, has healed itself:

Self-healing materials like this would be useful in so many places. They could keep tablets, phones and other everyday objects from sustaining nicks and scratches. Even NASA studies self-healing materials because they could reduce the need for costly and dangerous repairs in tough environments, i.e., space. Many labs around the world are working on different versions of this.

The material shown above, invented by a team of materials scientists from the IK4-CIDETEC Research Center in Spain, is one of the first that is able to heal itself without the help of heat, light, added chemicals or other interventions, according to Chemistry World. (Self-healing materials often need some kind of catalyst to trigger the changes in chemistry required to bond broken pieces back together again.)

Source: http://www.popsci.com/science/article/2013-09/watch-weird-gelatinous-material-heal-itself?src=SOC&dom=fb