Recent developments in the design of holders for transmission electron microscopes (TEM) have enabled widespread property analysis of nanostructures with unprecedented spatial resolution. It is now possible to routinely and reliably test the mechanical and electrical characteristics of a single carbon nanotube (CNT), for instance. Furthermore, due to the multitasking capability of TEMs, the study can even integrate simultaneous imaging and spectroscopical analysis. The combination of real-time gathering of structural, chemical, electrical and mechanical information provides an outstanding view of the materials' reactions when subjected to external stimulus such as current or heat.