  We study the dynamics of three particles in a finite interval, in which two
light particles are separated by a heavy ``piston'', with elastic collisions
between particles but inelastic collisions between the light particles and the
interval ends. A symmetry breaking occurs in which the piston migrates near one
end of the interval and performs small-amplitude periodic oscillations on a
logarithmic time scale. The properties of this dissipative limit cycle can be
understood simply in terms of an effective restitution coefficient picture.
Many dynamical features of the three-particle system closely resemble those of
the many-body inelastic piston problem.
