===== GRUB Password for Ubuntu =====

It's a good idea to add a password to the GRUB option for "recovery mode".  Without a password on this option, any knowledgeable person could log into recovery mode and change your passwords or do whatever they want.

To create this password as an md5 hash: 

  $ grub 
  
  grub> md5crypt
  
  Password: *********
  Encrypted: $1$sEOFN1$dalP1fzlFCHD4saxlnNzM/
  
  grub> quit


Copy this encrypted password and paste it in your grub config,

  sudo gedit /boot/grub/menu.lst

add the password to the recovery mode entry like this:

  title		Ubuntu 8.04, kernel 2.6.24-16-generic (recovery mode)
  root		(hd0,5)
  kernel		/boot/vmlinuz-2.6.24-16-generic root=UUID=********* ro single
  initrd		/boot/initrd.img-2.6.24-16-generic
  password --md5	$1$sEOFN1$dalP1fzlFCHD4saxlnNzM/

References:
http://www.linux.com/articles/53569