DeleteYouTubeAdContainers.user.js

// ==UserScript==
// @name     Delete YouTube Ad Containers
// @namespace    http://screwyoutube.com
// @version      1.0
// @description  Delete youtube's Ad Containers so it can't load ads into videos or on the page.
// @author       Xyberviri
// @include      http*://*.youtube.com/*
// @include      http*://youtube.com/*
// @include      http*://*.youtu.be/*
// @include      http*://youtu.be/*
// @run-at       document-end
// ==/UserScript==

function DeleteAds() {
  if(window.location.href.indexOf("watch?v=") < 0){
    return false;
  } else {
    try {
      document.getElementById("google_companion_ad_div").remove();
      }
    catch(err) {}
    try {
            document.getElementById("player-ads").remove();
        }
    catch(err) {}
    try {
       document.getElementById("video-ads").remove();
        }
    catch(err) {}
  }
};

setInterval(DeleteAds(), 500);