  We use cosmic microwave background (CMB) data from the 9-year WMAP release to
derive constraints on monodromy inflation, which is characterized by a linear
inflaton potential with a periodic modulation. We identify two possible
periodic modulations that significantly improve the fit, but it is unclear
whether this improvement is associated with a "signal" or with the scatter in
the measured angular power spectrum. The unmodulated potential is mildly
favored by standard model selection criteria. A modulated inflationary
potential can generate substantial primordial non-Gaussianity, of a specific
and characteristic form. For the best-fit parameters to the WMAP angular power
spectrum, the corresponding non-Gaussianity might be detectable in upcoming CMB
data, allowing nontrivial consistency checks on the predictions of a modulated
inflationary potential.
