Frog or horse?

[Tjalfe]

I'd say it is Frorse

[TnT]

I'd say it is Frorse

Of course! A Frorse!
A Frorse! Of course!
A frog and a horse,
for better or worse.
Fun with genetics,
without a remorse.

[Fat Tone]

I see a lot of these in my line of work, and I've never seen anything that so strongly flips your interpretation by simply rotating it 90 degrees. It's hard to make yourself see the other when flipped - well done I say.

[Mehen]

This is still one of my favority illusions:

http://web.mit.edu/persci/people/adelson/checkershadow_illusion.html

Jörg

That one bothered me so I did a quick photoshop check, and damn you it works

Go contrast go.