Its know that clear glass dots over a mili gives an optical illusion to zoom in… are there any other techniques that result in an optical illusion

The clear glass dot becomes a lense for the millie or anything you put it over.  The shape of the dot can have a huge effect on how it magnifies.  There really is no other technique we know of to do this.  A vortex marble uses a lense to make the vortex look as though it goes deeper than the marble actually is.