OK Linux geeks. Imagine you have:

• 5 or 6 Linux servers with their disks full of files
• A need to encrypt the files so that if the servers are lost in shipping, secrets are not loosed
• No extra disks and no extra servers to encrypt "onto"

How would you arrange to encrypt stuff "in place" where creating a mountable, encrypted filesystem isn’t really feasible?  Is there a magic wand I can wave, or do I really need to write my own script to PGP-crypt everything one file at a time and delete?  I’m assuming there isn’t a paid product that will encrypt "in place" but if there is, we probably would want it.

Thoughts?