Well, If you fully control your mails, I don't see how Google will be able to shut it down for no good reason.
We have depended too much on centralized powers for all most anything these days. It's high time we started decentralizing, owning our most cherished data, using peer-to-peer. If these can't be achieved on the current internet then we'll have to abondon it for safe internet
You can actually run your own server, but you need a domain name and probably your own (fixed) IP for it. Of course the smtp part should be properly configured with security in mind, (ie, password) so it doesn't become a spammer's gateway.
BUT, some ISPs are picky about you running your own server, even for private reasons. You might be forced to use non standard ports etc...
Email is decentralized in this fashion. There is also a similar solution for instant messengers, but people are stubborn and cling to proprietary products.