is an open source 3D graphics and animation software.
Examples of reflections on 8 spheres in cubic arrangement (by courtesy of Paul Tan-Rugh)
The spheres have been placed on a green plane. The sky is a blue hemi-sphere.
Movie (.avi) of a voyage inbetween the spheres: reflections_cube.avi
The original blender file (should be opened with 'blender'): reflections_cube.blend