Shape from shading algorithms have been around for a while. Dr. Mark J. Carlotto describes a simplified version using basic trigonometry (Sculptor's Photoclinometry page in the Pacific-Sierra Research Image Shape from Shading section). In that section, Dr. Carlotto describes the Berthold Klaus Paul Horn algorithm for read more »
PDS/EDR format is the image format used by NASA Planetary Data System and by ESA Planetary Science Archives. PDS images from various space missions are available at http://pds-imaging.jpl.nasa.gov/ and http://www.rssd.esa.int/index.php?project=PSA
With the PDS plug-in you can load images from these missions and others: