If you use Evernote, it’s possible that you store everything in there that you possibly can. Now, thanks to the MySMS service, you can also archive your text messages in your favorite everything-bucket.
MySMS ties into your Evernote account using the standard APIs. To use it, you need a MySMS account. This is kind of like iMessage for everyone (only one that works), letting you send and receive SMS messages from anywhere, including your desktop machine.
Once you have your SMSs in that system, it’s a simple to get them into your Evernote. All texts will be saved in a MySMS notebook, and a note will be created for each contact with whom you converse. New texts will be appended.
This is fantastic from an archiving point of view, especially as texts are just about the most ephemeral of communication media. And as your SMS messages are pretty much as bad as e-mail when it comes to confidentiality, I wouldn’t worry too much about piping them through a third-party service. Just don’t mention anthrax, or guns. Or anthrax guns.