I just had a comment form and end user that I thought
was rather inspired, I know it rarely happens, but nevertheless.

We had a situation where an email was deleted and removed from
trash. Now I recently bought a piece of software to address this
very issue. Sort of functions like Netware's Salvage utility (but
not as good obviously). In any case, it allows me to recover emails
that were once assigned to Davey Jones' locker. Now here's where
the observation comes in.

"If we are deleting emails, and they are still there aren't they
still taking up space which is the reason why we delete them?"

Not bad.