"SMS Backup +" claims to back up to Gmail but I read a blog about it that makes me think it works with any IMAP server, not just Gmail(???). Not sure if it can export to text.
Similar thoughts for "Super Backup : SMS & Contacts".
There are a few other blogs around about this, but I trust answers here much more than some of the stuff out there on the web. So what are you people using for something like this?
PS - Oh, "Text via Email" looks promising. I also see "SMS to Text". Few to try out, but I'd like to hear if anyone has experience with these or other solutions.