  The photometric precision, monitoring baselines, and rapid, even sampling
rates required by modern satellites designed for detecting the signal of
transiting exoplanets are ideally suited to a large number of applications in
high-energy astrophysics. I will exemplify this by discussing the results for
active galactic nuclei from Kepler and summarizing other high-energy results
from Kepler/K2. These precision instruments are currently underutilized for
high-energy applications despite their great potential, due in part to complex
systematics affecting the data. I will summarize these effects and mitigation
approaches, and conclude by discussing how the recently launched Transiting
Exoplanet Survey Satellite mission will differ from Kepler/K2 in ways
significant to the high-energy community.
