When you need to write and read email offline, you can hope you installed Google Gears, or just load up Thunderbird and grab your messages before you go. When webmail services go down, IMAP connections through Thunderbird usually still work. Even if you're a total Gmail devotee (like certain tip authors), Thunderbird is the smart app to keep on a USB stick and all your systems.

Thunderbird 3: With the new version 3.0 just out, Thunderbird has made it easier than ever to get an efficient, reliable desktop email client up and running in two, maybe three minutes. Import or enter your passwords once into KeePass, come up with a single, ultimate password or file 'key' to secure them all, and you'll never lose your data or log-ins again. There's a portable (Windows) version that runs off thumb drives, and since it's open source, it's likely to adapt to any new system that comes along. Versions of KeePass are available for Windows, Mac, and Linux systems, as well as on the iPhone, Android, and BlackBerry smartphone platforms. KeePass: It's the ultimate portable lockbox.

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