When Trouble was a kitten she spent many hours playing in the
bathroom.  Her favorite game involved the bath mat.  She would find a
small piece of foil covered paper or perhaps a coin and shove it under
the mat, back up a little, pretend something moved under the mat, and
then try to dive under the mat to attack the paper.  Usually only her
front legs would go under the mat, while her head stayed above, and
the mat would accordion in front of her little face.  This game made
the rubberized bottom of the mat age faster than normal and we had to
get new mats for our own safety.  The new mats were heavier than the
old ones, and the new rubber on the bottoms made it just too hard to
dive under so she stopped playing that game.  

Trouble is now four years old, and the new bath mats are not so new
anymore, and she found a penny that Hubby dropped in the bathroom.
And, oh joy!  Pennies slide faster over the new bathroom tiles!   I
thought she had forgotten about the bath mat game, but obviously not.
She is playing it again.  She looks the same doing it too because she
still has that wide kitten face.  She's just bigger and faster.      
Debra in VA