I use getmail (http://pyropus.ca/software/getmail/ http://pyropus.ca/software/getmail/) which isn't bound to a specific provider. Currently I backup my gmail an

I use getmail (http://pyropus.ca/software/getmail/ http://pyropus.ca/software/getmail/) which isn't bound to a specific provider. Currently I backup my gmail and fastmail accounts using this. Here is my daily process: - mount truecrypt container - run getmail for each account I want to backup (separate .conf files) - unmount container - sync offsite to rsync.net All of this runs on my raspberry pi 2 and it's really easy to setup (it's practically a bash file with 4 commands). The output is an mbox file which you can import into Thunderbird or any other client that supports them.