  We report on the current construction status of the IceCube high energy
neutrino observatory and possible future construction plans. With the
completion of the fourth construction season in Feb. 2008, the observatory is
now instrumenting half a cubic kilometer of ice, greatly increasing the horizon
for high energy neutrino detection. We briefly describe physics topics related
to cosmology, such as indirect searches for supersymmetric cold dark matter,
for slow and relativistic magnetic monopoles, GZK neutrinos and violation of
Lorentz invariance or Equivalence Principle. It is anticipated that upon
completion the new detector will vastly increase the sensitivity and extend the
reach of AMANDA to higher energies.
