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Since we're doing magic eyes now...
(sh.itjust.works)
My time has come!
The above stereographic image is for cross-eyed viewing (most stereograms are wall-eyed, so you may need to put your finger in front of your screen until this one comes into focus)
This is an image of Honolulu, Hawaii, published by NASA. Note Diamond Head (the volcanic crater) in the south.
Here are some other stereopairs published by JPL:
Wheeler Ridge, California
Mount Saint Helens
Salt Lake Valley, Utah
Wellington, New Zealand
Lots of people can really easily go cross-eyed and look at these with no practice whatsoever. Fewer people can do the parallel kind with no practice or with the amount of practice they've already done.