> None of the above.

I'd use encryption and try to convince others to as well, but I rely on email search too much. I'm sure a lot of people don't bother to 'tag' or 'label' their email, but instead rely on search to find messages with certain content in them. Maybe I'm wrong, but I don't see a way to have both with the server being unable to read the contents of the email to build a search index.