  We have performed systematic frequency analysis of the LMC Cepheids observed
by OGLE project. Several new types of pulsation behaviour are identified,
including triple-mode and amplitude-modulated double-mode pulsations. In ~10%
of the first overtone Cepheids we find low amplitude secondary periodicities
corresponding to nonradial modes. This is the first evidence for excitation of
nonradial oscillations in Classical Cepheid variables.
