This is only a part of generation 147 of the so-called L-pentomino,
which doesn't stabilise before the 2,497th iteration.

!Game of Life

!!GoL creates a grid as wide as the current screen of your desktop, plus a porch that adds to a total size of 160 x 90 by default. Create your own shapes by clicking the mouse, or by importing predefined ones. You may save your own creations in a special Shapes directory.
!GoL needs the font Selwyn to be present..