most of you know Lavabit and the story.
How about Comodo develops a service like Lavabit (or now safe-mail.net). Completely encrypted E-Mail service (I would suggest not to host the Servers for that Service in the US and also please don’t due it like Mega (not as secure as it seems). But don’t stop there, make a Encrypted E-Mail client which connects to the Encrypted Server with encrypted VPN. That would be true END-to-END encryption and really safe E-Mail. No need to develop a completely new client, fork Thunderbird and bring it to the next level. Thunderbird is a good feature rich E-Mail client, give it the “Comodo Touch”
P.S. Also combine it with an other suggestion of me, the Custom Android ROM but for that you would need to develop a E-Mail client for Android…