As email comes in, I either a) delete it b) reply to it (if I can do it in 2-5 mins, like Kevin Hoyt said) c) file it (if it's useful reference material) d) flag it for follow-up. I only check mail when I take a break in other projects. Most email that gets to the Flagged mailbox either gets deleted or added to Things as a todo. Once or twice a day I check Review and either reply or move to Things. Every few days I check Flagged and either reply, delete or move to Things.

Once you develop a bit of discipline about not spending much time on emails, it becomes easy.

I use Gmail as a repository for mailing lists and mostly just Mark As Read unless a subject line looks interesting. Later I can search Gmail for useful information. I don't have mailing lists coming to Apple Mail. I tend to check Gmail once every few days.

When i get an email i either answer it right away or right click, add category 'email', 'calls', 'work updates', 'work projects', or whatever, and then one more click to set the date, and quickly drag it to the 'to do' folder. Really fast and efficient.

Combined with outlook message rules, of which i have many to automatically add flags, categories, and most importantly put copies of messages into specified folders, it would take more effort to let things pile up in my inbox than it does to keep things totally streamlined.

Also, any email message put in a category gets added to the 'tasks' that sync to my blackberry.
Round trip on-top-of-it-at-last-ness.

I haven't changed. My home email is still under control. So, it must be something to do with the corporate style. I just get a lot of email that appears to require no immediate action, but will get referenced in a conversation, meeting or report over the coming weeks. The flip-side is that keeping a clear desk has never been easier. The only paper is the stuff that I produce for myself and most goes into the confidential waste within hours of printing.

I haven't used the mute feature but I'll try it on some threads going forward and I'll probably be a happy camper. Thanks dude.

Tyler, do you use GMail? Mute is a ridiculously handy feature. If I want to follow a list thread I archive, if not I mute. Never shows up in my inbox again. In my mind 'unread' and 'inbox' are totally divorced concepts. Inbox is stuff remaining to be dealt with, unread just means you haven't read it, usually because the subject line was sufficient (either to get the message or decide you don't care).

The rest of GTD used to be pretty messy, but a lot of applications have emerged to round out its application. I don't generally use GTD-specific tools, but rather others that fit my workflow. If they are open source or have an API, that's even better so I can really work them into how I think. Remember the Milk is my to-do list, and Evernote is my filing system. I use FreeMind for mind mapping, but I'm not as attached to it as the other two.

Curiously enough, my Gmail is a train wreck. I don't use it that often, and when I do, I've found that the search is so high quality, and fast, that I get what I need with little effort. Generally speaking, I think the concept of tags has really made life easier across all products that use them (versus categories).

I understand that I could get something similar using Things or another to do tool with delivery dates, but I find that priorities change so often due to changing client priorities, the time to keep on updating the delivery dates for 40-50 small tasks simply isn't worth it.

In short, I find a few items in my email inbox another useful reminder of certain key tasks in the same way you might stick a note on the fridge to remind you to do something.