We present a discovery and observation of an extraordinarily bright prompt optical emission of the GRB 060117 obtained by a wide-field camera atop the robotic telescope FRAM of the Pierre Auger Observatory from 2 to 10 minutes after the GRB .
We found rapid average temporal flux decay of \alpha = -1.7 \pm 0.1 and a peak brightness R = 10.1 mag .
We interpret the shape of the lightcurve as a transition between reverse and forward shock emission .