Cathode rays, accelerated by tens of thousands of volts or more, have had immense scientific and technological value in the hundred years since Joseph John Thomson used them to discover the electron. The most familiar use of these electron beams is in cathode‐ray tubes—as used in television sets and computer displays, for example. Electron microscopy, a less familiar use, has been a keystone method for visualizing the structure of materials on the atomic level, and continues to offer exciting developments. Electron beams have also found an important role in patterning semiconductor chips, and they may even supplant optical beams as a basis for lithography in the 21st century. Before the discovery of electrons, photons dominated microscopy. Now it seems that in both microscopy and lithography, electrons will take over. More power to rest mass! In this article, I give a glimpse of the state of the art in electron microscopy and lithography, and point out where I believe these fields are going.