[sdrothrock]

"unsendable" makes me think that the e-mail cannot be sent, rather than what the service actually offers -- e-mails that can be retrieved AFTER they are sent.

The idea of mutable e-mails scares me a lot, even if they're immutable after the receiver opens them.

[miniunicorn]

Haha, maybe I should create an email client that just doesn't work. Then emails would certainly be unsendable.