How to watch restricted videos on youtube without signing in?

Many of you might have come across this situation when youtube wants you to sign in and confirm your age before watching the video, but it really sucks signing in all the time, so here is a short trick with the help of which you can bypass this youtube's restriction without signing in!
have a look..

Steps:

1. First get the Url of video you want to watch. As shown below.

http://www.youtube.com/watch?v=4Xkh6j7RMqk 

2. Then copy the Video Id. For above link video Id is 4Xkh6j7RMqk


3. Now paste the Video Id in the link given below.

http://www.youtube.com/v/VideoId?fs=1

Replace VideoId with the Id you copied in Step 2

4. Now the url will become as shown below.

http://www.youtube.com/v/4Xkh6j7RMqk?fs=1

5. Done.