[cryptical]

Formatting doesn't help, and overwriting isn't foolproof.

It depends on what your threat model is and how much it's worth to your adversaries to recover your data.

E-mail traverses several machines to get to you typically, so even securing the data on your mailbox machine may not be good enough.

End-to-end encryption works. It's a little extreme for most people, and there are all sorts of gotchas in implementation to worry about, but if you have the need you can afford the solution.

[cynwoody]

End-to-end encryption works. It's a little extreme for most people, and there are all sorts of gotchas in implementation to worry about, but if you have the need you can afford the solution.

This is true. You just have to make sure the wrong people don't find out the pass phrase.