While installing Ubuntu 11.10, you will be offered to encrypt the home folder so that you keep your files and folders secured. If you haven't opted for this option during Ubuntu 11.10 installation, you can easily do it now via the command line by following these instructions:
1. Open the terminal and install first the ecryptfs-utils command line utility with this command:
sudo apt-get install ecryptfs-utils
2. To encrypt your home directory, use now this command:
sudo ecryptfs-migrate-home -u username
Replace username with your own username. After you login, a window like this will pop-up (it may take time to appear):
Click Run this action now and enter your user password you use to login to generate a passphrase for your home directory.
Your home directory is now encrypted. If you forget your passphrase, you can recover it with this command: