If you click on the cloud photograph to the right and think perhaps it is time you wore glasses, you are right.
But your eyesight is probably fine – it is the picture that is playing tricks. It is an anaglyph image, which creates a stereoscopic 3D effect when viewed with two-colour glasses, usually cyan and red. Anaglyph images are made up of two colour layers, superimposed, but offset with respect to each other to produce a depth effect.
This example is part of a series of cloud pictures taken by Ben Orona. He says the two photographs which make up each 3D image were taken hundreds of feet apart, which helps give them their depth.
However, you will need a pair of anaglyph cyan-red glasses to see the 3D effect. You can buy them online – here, for example – but all the sites we found sold them in packs of five or ten. You may be able to buy them singly on eBay.