KLS Mail Backup makes email, browser backups a snap
KLS Mail Backup takes the hassle out of backing up and restoring profile data from seven different programs: IE, Firefox, Thunderbird, Outlook Express, Seamonkey, Live Mail, and Windows Mail. Select the applications and profiles you want to back up, check the items you want to store, and run your job.
Your archives are automatically zipped, and Mail Backup will maintain a version history by default. Completed back ups can be browsed by clicking the archive tab on the right side of the main application window. Versioning options are completely configurable: you can specify the number of archives to keep or the number of days to store them before deleting.
Though not described as portable on the KLS Soft web site, I had no issues running Mail Backup from a shared folder on my network.
Opera, Chrome, and Outlook aren't currently supported, but Mail Backup is very actively developed. Since KLS adds new applications to Mail Backup as plugins, it may only be a matter of time before they're included.
Mail Backup is free for personal use and runs on Windows 2000 or newer (including x64 builds).