tickle.js

var f = function() { 
  var v = speechSynthesis.getVoices().filter(function(v) { return v.name == 'Hysterical'; })[0], 
      s = ["ahahahaha", "stop it", "don't tickle me"], 
      t = new SpeechSynthesisUtterance(s[~~(Math.random()*s.length)]); 
  t.voice = v; speechSynthesis.speak(t);  
};
Array.prototype.slice.call(document.querySelectorAll('a')).forEach(function(a) {
   a.addEventListener('mouseover', f); 
});