Encrypted file system for Linux

dd if=/dev/urandom of=/dev/sda1 bs=1M
losetup -e aes-256 /dev/loop0 /dev/sda1
mkfs.ext3 /dev/loop0
mkdir /mnt/crypto
echo "/dev/sda1 /mnt/crypto ext3 noauto,encryption=aes-256 0 0" >> /etc/fstab