I’ve switched e-mail clients three times in the last 30-days in an effort to seamlessly integrate my work life with my personal life.

Anyone who’s gone through this change can tell you its quite unnerving. Batches of e-mails delivered all at once and then lost in the blink of an eye. E-mails you’ve read and filed come through as new.

And when it comes to calendars, don’t even get me started. Everything is lost in the migration and then looks like a 17 car pile up on the highway. Calendared events overlap on top of each other with reckless abandonment when you switch from one client to the next.

It all started when I realized Dotmac wasn’t compatible with my corporate solution, so I switched to Entourage which didn’t synch with my iPhone (and I’m not giving up my God-phone). I ultimately migrated to Gmail which I love, but the mail client is only accessible to me on my computer when I have an internet connection. Since I’m not always interested in viewing my mail on my iPhone this is rather important. It also means my productivity is cut in half on my hour long commute to and from work. But that’s all about to change.

On January 27th, Google rolled out an experimental feature in Gmail Labs. So even if you’re offline, you can open your web browser, go to gmail.com, and get to your mail.

Once you turn on this feature, Gmail uses Gears to download a local cache of your mail. As long as you’re connected to the network, that cache is synchronized with Gmail’s servers. When you lose your connection, Gmail automatically switches to offline mode, and uses the data stored on your computer’s hard drive instead of the information sent across the network. You can read messages, star and label them, and do all of the things you’re used to doing while reading your webmail online. Any messages you send while offline will be placed in your outbox and automatically sent the next time Gmail detects a connection. And if you’re on an unreliable or slow connection (like when you’re “borrowing” your neighbor’s wireless), you can choose to use “flaky connection mode,” which is somewhere in between: it uses the local cache as if you were disconnected, but still synchronizes your mail with the server in the background.

Watch the video, learn more and enjoy.