  We compute the non-Gaussianities that arise in single field, slow roll
inflationary models arising from arbitrary homogeneous initial states, as well
as subleading contributions to the power spectrum. Non Bunch-Davies vacuum
initial states can arise if the transition to the single field, slow roll
inflation phase occurs only shortly before observable modes left the horizon.
They can also arise from new physics at high energies that has been integrated
out. Our general result for the bispectrum exhibits several features that were
previously seen in special cases.
