Is it currently possible to use gnupg to automatically encrypt/decrypt files attached using the org-attach feature? If not, would it be hard to implement? 

The org-crypt feature is great and I use it all the time to keep sensitive data in my reference file, but when I need to archive files (often scan of documents) I would also like to have the ability to automatically encrypt them when filing, and them decrypt them when using org-attach to open the file.

Thanks,

Marcelo.