Solar Eclipse Sharp and Fuzzy Shadows

During a solar eclipse, your shadows will look "weird". This is because the sliver shape of the sunlight will cause shadows to be sharp in one direction while still being fuzzy in others. Normally, your shadows are a little fuzzy because the sun is not a point source of light.

This model should allow you to demonstrate and better understand this strange behavior. Disclaimer: (I have not tested this myself).

A better explanation can be found at 10:34 of this video.