How to automatically play and loop a youtube video

I like to do this every once in a while when I am practicing a song or if I just want to listen to the same song over and over again. But I always forget how and have to look it up. So now I can just look back here. First you need the video ID, this is in the of any normal youtube video you are watching. For example:

http://www.youtube.com/watch?v=Ed49S2nyBD0

The ID from this video is Ed49S2nyBD0. Just replace the that ID in the url below and form the URL the same as below and autoplay and loop till your heart is content. 😛

http://www.youtube.com/v/Ed49S2nyBD0&autoplay=1&loop=1

I should note that there are some videos which won’t play on other sites, there may be a way around that by passing other values in the urlstring, but I don’t know it. The video referenced here is a zac brown band recording. If you try and do this with the ‘official video’, it won’t play and will make you go watch it on the site.