Why It is Impossible to Tune a Piano.

Here is a 'random curious stuff' item, per the MindBlog description above.  I want to pass on this great explanation of why physics requires that piano notes have to be slightly out of tune, except for the octave, resulting in the equal temperament tuning system most piano tuners use. I suggest you expand the video to full screen, and pause it occasionally to catch up with its rapid pace.