Dramatic changes can be expected within the next few years in science that depends on synchrotron radiation today. An analysis of available data on short-pulse, high-intensity x-ray and electron sources indicate possibilities for imminent developments with x-ray free-electron lasers (driven primarily by the high energy physics community), and with table-top femtosecond x-ray sources based on laser-induced plasmas and wakefield acceleration. New sources could generate femtosecond x-ray pulses with as much as 12 orders of magnitude increase in peak brilliance and power over third-generation synchrotron storage rings. Such developments would create revolutionary new research opportunities in condensed matter physics, biology and medicine. Some of the possibilities are discussed here. ©1999 American Institute of Physics.