  Using a new uniform sample of 824 solar and late-type stars with measured
X-ray luminosities and rotation periods we have studied the relationship
between rotation and stellar activity that is believed to be a probe of the
underlying stellar dynamo. Using an unbiased subset of the sample we calculate
the power law slope of the unsaturated regime of the activity -- rotation
relationship as $L_X/L_{bol}\propto Ro^\beta$, where $\beta=-2.70\pm0.13$. This
is inconsistent with the canonical $\beta = -2$ slope to a confidence of
5$\sigma$ and argues for an interface-type dynamo. We map out three regimes of
coronal emission as a function of stellar mass and age, using the empirical
saturation threshold and theoretical super-saturation thresholds. We find that
the empirical saturation timescale is well correlated with the time at which
stars transition from the rapidly rotating convective sequence to the slowly
rotating interface sequence in stellar spin-down models. This may be hinting at
fundamental changes in the underlying stellar dynamo or internal structure. We
also present the first discovery of an X-ray unsaturated, fully convective M
star, which may be hinting at an underlying rotation - activity relationship in
fully convective stars hitherto not observed. Finally we present early results
from a blind search for stellar X-ray cycles that can place valuable
constraints on the underlying ubiquity of solar-like activity cycles.
