I'm glad that you liked it!   ^_^

 The EncFS was my choice to the LiveCD solution, because it is more space efficient, but within the Amazon cloud computing environment, you may want to choose the LUKS (cryptsetup command), which encrypt a entire partition (or disk / EBS volume), and not only a few directories / files.

 The EncFS will work, no doubt, but for the EC2 / EBS, the LUKS seems more adequate. You can have your entire /home (or /mnt) encrypted.

 Just connect the EBS volume in your instance, and "cryptsetup" it!

 LUKS - http://code.google.com/p/cryptsetup/

 BTW, do not forget to read the documentation and test 10 times all the alternatives!! And, I'm available to help with LUKS if you wish...   


 References:

 Encrypting /mnt using cryptsetup on Ubuntu 8.04 Hardy on Amazon EC2 (2008):
 http://groups.google.com/group/ec2ubuntu/web/encrypting-mnt-using-cryptsetup-on-ubuntu-7-10-gutsy-on-amazon-ec2?pli=1

 Updated version - Encrypting Ephemeral Storage and EBS Volumes on Amazon EC2 (2009):
 http://alestic.com/2009/10/ec2-disk-encryption


 Just for the record, the standard Ubuntu "cryptdisk" utility is the eCryptFS, which can be used to also encrypt the entire /home/user directory.

 eCryptFS - https://launchpad.net/ecryptfs

Best!
Thiago