  The luminescent bolometer, proposed in 1988, is now seriously considered for
several applications in nuclear and particle physics: dark matter searches,
double beta decays, low energy neutrino physics, heavy ion physics... It is
also a very promising device for basic condensed-matter physics and chemistry
experiments, and may lead to astrophysical applications. The luminescent
bolometer is based on the simultaneous detection of light and phonons, allowing
for particle identification and for a detailed study of the detector response.
Digitized analysis of the signals produced in several sensors installed on the
same crystal is then a very powerful tool. Superconducting sensors allow to
detect the scintillation light pulse followed by the delayed front of phonons,
and can be extremely sensitive leading to single photon counting in the visible
range. They also provide information on the position of the event inside the
absorber, and can be fast enough for all proposed applications. The luminescent
bolometer, with superconducting sensors, appears extremely promising for real
time $solar$ neutrino experiments based on new indium single crystal
scintillators. We focus on this particular application, discussing the status
of the art as well as open problems and presenting an updated description of a
full scale real time solar neutrino experiment sensitive to the low energy
sector. Other applications of the luminescent bolometer (e.g. spectroscopy or
neutrino detection at reactors), involving indium compounds and other single
crystal scintillators, are equally considered and discussed in detail.
