Indexing e-mails

The facility to index files is really useful, allowing you to access documents from a database without having to import it. It allows editing & saves space.
I was wondering if it was possible to do something similar with e-mails so that you can index the content of a mailbox to organise it into smart folders etc. without importing the e-mails (Mail does display threads better). If this is possible, where do the mailboxes hide?

Bill

No. While you can do it, you should not. It is not going to be a good experience, if you try this. Trust me.

Warning heeded, it would be good though!

Bill

It would take much more development to support this behavior.