  We present a detailed analysis of all archival INTEGRAL data of the accreting
X-ray pulsar Vela X-1. We extracted lightcurves in several energy bands from 20
keV up to 60 keV. The lightcurves show that the source was found in very active
as well as quiet states. During the active states several giant flares were
detected. For these states spectra between 5 keV and 120 keV were obtained. The
spectra of the active states were found to be significantly softer than those
from the quiet states. We performed a statistical analysis of the flaring
behavior. The resulting log-normal distribution of the intensity of Vela X-1
shows that the source spends most of the time at an average flux level of 300
mCrab but also that the distribution extends well up to more than 2.0 Crab.
