User:Randfan/Optical Illusions I like

A stylised version of the channel in Waterfall with ambiguous 3-dimensional detail added

The Penrose triangle

An example of how an object could appear to be invisible through the use of mirrors

An optical illusion. Square A is exactly the same shade of grey as square B. See Same color illusion

The Scintillating grid illusion or Hermann grid illusion. Dark spots seem to appear and disappear very quickly at the intersections

Simultaneous Contrast Illusion. The grey bar is the same shade throughout

An optical illusion. The two circles seem to move when the viewer's head is moving forwards and backwards while looking at the black dot.

Floor tiles at the Basilica of St. John Lateran in Rome. The pattern creates an illusion of three-dimensional boxes.

Magic tap, which appears to float in the sky with an endless supply of water. In actuality, there is a pipe hidden in the stream of water.