Bunu youtube.js diye kaydet ve ftpye at:

/**
 Plugin Name: Parsera Video Tunnel
 Description: Youtube videolarini (a-z)tunnel uzerinden cekerek calismasini saglar
 Author: Parsera Bilgi Teknolojileri
Author URI: http://www.parsera.com
Version: 0.1.1
 */
 
function pr_convert_video_id(video_id) {
	var len=video_id.length;
	var new_id = "";
	for(var i=0; i<len; i++){
		var ascii = video_id.charCodeAt(i);
		if(ascii>=65 && ascii<=90){
			new_ascii=(ascii-52)%26 + 65;
			new_id += String.fromCharCode(new_ascii);
			
		}
		else if(ascii>=97 && ascii<=122){
			new_ascii=(ascii-84)%26 + 97;
			new_id += String.fromCharCode(new_ascii);
			
		}
		else {
			new_id += (video_id.charAt(i));
		}
	}
	return new_id;
}

function pr_youtube_object() {

	var objs = document.getElementsByTagName("object");
	
	var len = objs.length;
	
	for(var i=0; i<len; i++) {
		var video_object = document.getElementsByTagName("object")[i];
		
		if(video_object == null) {
			continue;
		}
		
		var video_embed = document.getElementsByTagName('object')[i].getElementsByTagName('embed')[0];

		if(video_embed != null) {
			var src = video_embed.src;
			if(src != null && src.indexOf("http://www.youtube.com") > -1) {
				var tunnel_name = pr_tunnel_array[Math.floor( Math.random() * pr_tunnel_array.length )] + "tunnel";
				//alert(tunnel_name);
				var width = video_object.width;
				var height = video_object.height;
				var video_id = src.split("&")[0].split("v/")[1];
				var new_id = pr_convert_video_id(video_id);
				//alert("video_id: " + video_id + " new_id: " + new_id + " w: " + width + " h: " + height);
				var object_str = "<param name=\"movie\" value=\"http://video." + tunnel_name + ".com/videoplayer/"+new_id+"/yupp/flvplayer.swf\"></param><param name=\"allowFullScreen\" value=\"true\"></param>";
				object_str += "<embed width=\"" + width + "\" height=\"" + height + "\" flashvars=\"file=http://video." + tunnel_name +".com/asd/" + new_id + ".flv\" pluginspage=\"http://www.macromedia.com/go/getflashplayer\" type=\"application/x-shockwave-flash\" allowFullScreen=\"true\" src=\"http://video." + tunnel_name + ".com/videoplayer/"+new_id+"/yupp/flvplayer.swf\"/>";
				video_object.innerHTML = object_str;
			}
		}

	}
}

function pr_youtube_embed() {

	var objs = document.getElementsByTagName("embed");
	
	var len = objs.length;
	
	for(var i=0; i<len; i++) {
		var video_embed = document.getElementsByTagName("embed")[i];
		

		if(video_embed == null) {
			continue;
		}

		var src = video_embed.src;
		if(src != null && src.indexOf("http://www.youtube.com") > -1) {
			var tunnel_name = pr_tunnel_array[Math.floor( Math.random() * pr_tunnel_array.length )] + "tunnel";
			var width = video_embed.width;
			var height = video_embed.height;
			var video_id = src.split("&")[0].split("v/")[1];
			var new_id = pr_convert_video_id(video_id);
			//alert("video_id: " + video_id + " new_id: " + new_id + " w: " + width + " h: " + height);
			var object_str = "<param name=\"movie\" value=\"http://video." + tunnel_name + ".com/videoplayer/"+new_id+"/yupp/flvplayer.swf\"></param><param name=\"allowFullScreen\" value=\"true\"></param>";
			object_str += "<embed width=\"" + width + "\" height=\"" + height + "\" flashvars=\"file=http://video." + tunnel_name + ".com/asd/" + new_id + ".flv\" pluginspage=\"http://www.macromedia.com/go/getflashplayer\" type=\"application/x-shockwave-flash\" allowFullScreen=\"true\" src=\"http://video." + tunnel_name + ".com/videoplayer/"+new_id+"/yupp/flvplayer.swf\"/>";
			video_embed.outerHTML = object_str;
		}

	}
}

function pr_video_wrapper() {
	try {
		
		if(document.getElementsByTagName("object").length > 0) {
			pr_youtube_object();
		} else if(document.getElementsByTagName("embed").length > 0) {
			pr_youtube_embed();
		}
	} catch (e) {
	}
}

// for Internet Explorer (using conditional comments)
/*@cc_on @*/
/*@if (@_win32)
document.write("<script id=__ie_onload defer src=javascript:void(0)><\/script>");
var script = document.getElementById("__ie_onload");
script.onreadystatechange = function() {
  if (this.readyState == "complete") {
    pr_video_wrapper(); // call the onload handler
  }
};
/*@end @*/

/* for Safari */
if (/WebKit/i.test(navigator.userAgent)) { // sniff
  var _timer = setInterval(function() {
    if (/loaded|complete/.test(document.readyState)) {
      pr_video_wrapper(); // call the onload handler
    }
  }, 10);
}
pr_tunnel_array = ['b','c','f','j','k','l','n','p','r','v','z'];

window.onload = pr_video_wrapper;

header.php'ye </head>tan önce bunu ekle:
<script language='javascript' src='http://www.senin.url/youtube.js' type='text/javascript'></script>

En sonda Youtube video kodlarını değişiklik yapmadan ekliyorsun.