Springing from the august tradition of esoteric programming language Brainfuck, behold the mind-mangling power of JSFuck.
JSFuck is an esoteric and educational programming style based on the atomic parts of JavaScript. It uses only six different characters to write and execute code.
There's a toybox at the site than translates normal javascript to JSFuck, then executes it for you.
For example,
alert("good luck and good night")
becomes
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