So You Like Ambiguity

The duck-rabbit illusion is an oldie but goodie. This new square-cylinder illusion will make you second guess your visual cortex. It's a square, it's a circle, it's both, it's neither.

The Ambiguous Cylinder Illusion wins the illusion of the year contest2016

 gif:

https://lovelace-media.imgix.net/uploads/892/dae451c0-24fa-0134-0cab-0a0b9a139ea7.gif?

Video:

https://m.youtube.com/watch?v=oWfFco7K9v8