Questo è un esempio classico:
http://digilander.libero.it/armagedd...protected2.htm
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document.write(String.fromCharCode(60,84,65,66,76, 69,32,65,76,73,71,78,61,34,99,101,110,116,101,114, 34,32,66,79,82,68,69,82,6

1,52,32,87,73,68,84,72,61,53,48,37,32,67,69,76,76, 83,80,65,67,73,78,71,61,48,32,67,69,76,76,80,65,68 ,68,73,78,71,61,51,48,62,60,

84,82,62,60,84,68,32,66,71,67,79,76,79,82,61,34,35 ,48,48,67,67,54,54,34,62,60,102,111,110,116,32,102 ,97,99,101,61,34,118,101,

114,100,97,110,97,34,32,115,105,122,101,61,50,62,7 3,108,32,115,111,114,103,101,110,116,101,32,100,10 5,32,113,117,101,115,1

16,111,32,102,105,108,101,32,72,84,77,76,32,60,110 ,111,115,99,114,105,112,116,62,109,105,115,112,105 ,97,99,101,115,111,110,

111,105,110,118,105,110,99,105,98,105,108,101,60,4 7,110,111,115,99,114,105,112,116,62,32,232,32,112, 114,105,118,97,116,11

1,32,101,32,110,111,110,32,100,105,115,112,111,110 ,105,98,105,108,101,32,97,108,32,112,117,98,98,108 ,105,99,111,46,60,98,11

4,62,71,114,97,122,105,101,46,60,98,114,62,60,98,6 2,65,114,109,97,103,101,100,100,111,110,60,47,98,6 2,60,47,84,65,66,76,69,6

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