One of the oft-quoted laws of time management is "touch each piece of paper only once." The idea is simple. You don't waste time dealing over and over with things that you've already dealt with once. When you see something, you should be able to react appropriately and move on to the next thing.

But in the on-the-go digital world, does this still work? Can you handle each piece of data only once, whether it's at home, at the office, or on your PDA?

With the right tools, yes.

First, let's look at email. Most people still use POP3 email, which doesn't travel well with you to other locations. The idea behind POP3 is that your email only briefly resides on the mail server before being downloaded permanently to your PC. You can choose to leave messages on the server while you're on the road, but  you'll have to download them again when you get home. Or, you can download things permanently from wherever you are, but end up with fragmented, impossible-to-search mail store. Thus, it's almost impossible to see each message only once (until you have to search for it for reference) using POP3.

Until recently, there was no really easy solution for this. Gmail changed a lot of that. With Yahoo following their lead, it's now reasonable to expect to keep all your email online and use webmail now matter where you are. Webmail from Gmail (haven't tested Yahoo, and they're getting ready to change their webmail interface anyway) is a pleasure to use on the desktop and works almost as well on a handheld (though I can't get file uploads to work on Gmail in Blazer). But the key to this is that when you file a message or delete a message in any location, you see the same result in other locations. Handle each email only once.

As nice as they are, webmail solutions do have some limitations. If you'd prefer to continue using your favorite desktop mail client (or in my case, Chatter on my Treo; push email rocks) there is a better way. IMAP.

The IMAP4 protocol is more advanced than POP3, but more importantly it's designed to keep messages on the server and access them from other locations. Your inbox and other folders reside on the server and your desktop client just mirrors what's on the server. If you use an IMAP mail server (I use fastmail.fm, but many Internet Service Providers provide IMAP for free if you ask) you can get the "read once, file everywhere" benefits of webmail while keeping the power of your desktop mail client. Just set up all your mail clients to access the same IMAP mail store and you're all set.

For what it's worth, I only have two folders other than the standard inbox, drafts, sent, etc. Those are Filed and Respond. If I need to do something with a message or if it's just too long to read right now, it goes in Respond. If I need to keep it around for near-term reference, it goes in Filed. If it is neither, it gets deleted. Period.

My setup is a little more complicated than that, however. I still use my Gmail account as my primary mail store and my central archive. I have Gmail set to automatically forward anything that isn't spam to my Fastmail IMAP account. So even if I delete stuff in Fastmail, every email sent to me is archived at Gmail. So if I really need to retrieve something for reference in a year, I can get to that from anywhere. But the email store I normally see remains sparse, light and agile.

So that covers email and how to see each message only when you need to do something about it. What about web sites? I read dozens of sites every day to stay on top of mobile technology. How do I ensure that I'm not distracted by articles I've already read?

This was almost impossible before RSS. But now it's possible to keep track of what you've read no matter where you are. The key is to use a web-based RSS aggregator.

Quite a few sites will consolidate your RSS feeds into a single web-based interface, but only two I've found offer really good both desktop and mobile interfaces. If I can't read my RSS feeds comfortably on my Treo when I'm on the go, this system doesn't work.

The two mobile-friendly, desktop-powerful aggregators I've found are Bloglines and Newsgator. Both are free for desktop use, and Bloglines is also free for mobile use. Mobile use requires a small monthly fee with Newsgator, but I prefer Newsgator anyway. The key difference is that Bloglines assumes you've read all the messages on a page as soon as they're displayed, while Newsgator requires that you explicitly mark a page as read. This makes all the difference if you tap on a link to a story in the middle of a page in Blazer. Palm web browsers (so far, we'll see what having the makers of NetFront owning Palm OS does) typically don't support tabbed browsing, and coming back from reading a story to find the rest of the articles from that site gone gets old pretty quickly.

So I read my newsfeeds in IE (the beta of IE 7 rocks) at work and at home, and I Blazer on my Treo. My email comes into Chatter on my Treo, Fastmail's web interface at work and Outlook at home. But no matter which tool I use, no matter where I am, I have no digital redundancy. My information follows me, not the other way around.