Over the last two years, a SLAC-Aarhus-Ferrara-CalPoly collaboration has performed channeling experiments using bent silicon crystals at the SLAC End Station A Test Beam as well as the FACET accelerator test facility. These experiments have revealed a remarkable channeling efficiency of about 24% under our conditions, as well as shown the dechanneling rate to be independent of the beam energy; an unexpected result. We have been able to test recent predictions of intensity modulations in the “dechanneling tail” of positrons and electrons undergoing channeling. In our most recent experiment we have attempted to measure the spectrum of channeling and volume-reflection gamma radiation. The goal of this series of experiments is to develop a crystalline undulator capable of producing narrow-band gamma rays with electron beams. Such a device could have applications in gamma-ray radiography as well as spectroscopic applications. The talk will introduce the physics of channeling and related phenomena as well as the results of the experiments. I will describe the work in the broader context of possible applications in the field of accelerator physics and technology and radiation sources.