Now this is pretty cool, you can watch YouTube Videos with your online friends. I mean you all can watch the same video and chat with each other while watching it. You can even rewind and fast forward the video. Moments ago I wrote about YouTube Instant which helps you search for videos in real time.
YouTube Social give you a social option to watch YouTube Videos with your friends virtually. You can connect to the site using Facebook Connect and invite your friends to the room or just invite them by using a short url. I tried it with couple of my friends and I was really Cool to watch videos and talk about it in the chat from the right sidebar.
Try YouTube Social Yourself.