  The neutron-star inner crust is assumed to be superfluid at relevant
temperatures. The contribution of neutron quasiparticles to thermodynamic and
transport properties of the crust is therefore strongly suppressed by the
pairing gap. Nevertheless, the neutron gas still has low-energy excitations,
namely long-wavelength collective modes. We summarize different approaches to
describe the collective modes in the crystalline phases of the inner crust and
present an improved model for the description of the collective modes in the
pasta phases within superfluid hydrodynamics.
