In general, Inbox Zero is a good concept and I think it can be important for many people. But if you find yourself having trouble maintaining it, consider giving it up. I gave up the idea before I even heard of GTD and Inbox Zero. Once, it seemed like a good idea to have a clear email Inbox, so I tried filing all the emails that came in, answering the ones that needed answering. I was adding another tiresome chore on top of a bunch of other tiresome chores. Inbox Zero is not for me, and it might not be for you. Here are Simple_ton's realizations why:
Mine is, so I use it as a reference. It's very useful for me to be able to search on keywords and mail address, etc. If I have to store a certain email somewhere, where do I put it? If I file it by date, I break up the thread of conversation. If I file it by name, I end up with a folder full of disjointed emails. Maybe I could file it by topic, but then I have a list of folders that runs out the room. I like my email to be in one big mushy pile. Please leave it there.
There is this one guy, there always is, that sends out the twitter style email carpet bomb blitzkrieg. His emails skew my search results, so I have a special folder for him. But he's a special case, so when something comes up that involves an email from him, it's easy enough to search my inbox and fill in the gaps with his twitter-like messages.
Once, we were 2 weeks out from a deadline on a really huge project. Very busy. So I tried it out: I will check and answer email only twice a week. Guess what. Everything was OK. Sure, there were some panicky emails that came in and I didn't know about. But when a decision really needed to be made, and I was the only one that could make it, guess what else happened. They called me. I answered their question and we were both back to work. Maybe I had to search through some emails to really get their point. And Yes, all the emails were right there, ready to be filtered and scanned while on the phone. A couple people were miffed I wasn't on top of my email. I politely apologized (I work in Japan) for not checking my mail, and said I was busy trying to ensure delivery. Then they shrug, maybe moan and groan a bit while I type, and the conversation goes on.
I told my daughter she should keep track of her emails and check regularly. Kind of a "Get your inbox to zero" statement. She immediately shot back with, "But I saw your inbox, and you had over 100 unread emails!" My reply? "It's OK for me. I get the idea what they're talking about, and I know what each of those emails says." Of course, email carpet bomber guy is different. But I already put him down as a special case. His email headers are usually from an email sent 2 weeks ago, anyway. Apply and encourage use of the following rule: The person you email should be able to read the header and know what the email is about.