Adaptive 3D Edge Styles 

Edges in 3D charts provide contrast at relatively low densities, but are automatically turned off when they would interfere with the interpretation of the graphic.

In[1]:=

X data = RandomVariate[NormalDistribution[0, 1], {10000, 2}];

In[2]:=

X List[Table[Histogram3D[data, i, ImageSize -> 250], {i, {25, 50}}]]

Out[2]=