Disable sudo password ubuntu

I am sure you will agree with me that every time we enter "sudo" we are prompted with password request! Well, we can get around it this way:
Open shell and type:

user@backbox:~$ sudo visudo

Add the following line to the END of the file:

<username> ALL=NOPASSWD: ALL

Replace <username> with your user name (without the <>).

Example:

 grnet ALL=NOPASSWD: ALL

Hit Ctrl + o + Enter to confirm, and Ctrl + x to save and exit.
That's it from now on, everytime you type "sudo", you wont be prompted for password!

sumbr : http://wiki.backbox.org/index.php/Sudo_without_password