underscore_throttle.js

//click count
var count = 0;

//this is the handler
var onClick = function(e){
  alert('button clicked ' + (++count) + ' times');
};

//this is the "throttled" function,
// that is a function that executes only once in a given timespan (here: 200ms)
var throttled = _.throttle(onClick, 200);

//here the handler is bound to the event
document.getElementById("myBtn").addEventListener("click", throttled);