I'm a fan of Javascript. It has proper lambdas, true lexical scope, will soon have TCO, and is a really flexable language.

But it's not without its warts, and this is one of the worst. Although it's sometimes fun to mess with, nonetheless.

To see this taken to one of its logical extremes, check out If Hemmingway Wrote Javascript's entry for Douglas Adams:

  // Here I am, brain the size of a planet, and they ask me to write JavaScript...
  function kevinTheNumberMentioner(_){
    l=[]
    /* mostly harmless --> */ with(l) {
 
      // sorry about all this, my babel fish has a headache today...
      for (ll=!+[]+!![];ll<_+(+!![]);ll++) {
        lll=+!![];
        while(ll%++lll);
        // I've got this terrible pain in all the semicolons down my right hand side
        (ll==lll)&&push(ll);
      }
      forEach(alert);
    }
 
    // you're really not going to like this...
    return [!+[]+!+[]+!+[]+!+[]]+[!+[]+!+[]];
  }