It took me a while, but ever since I've gotten my head around Smart Folders (and Smart Playlists and Smart Groups, etc.), I've started to think about the way I use my Mac a bit differently.

Clearly iTunes is the winner in this regard (watch for an upcoming multi-part series about Smart Playlists on The Merlin Show), but the Finder, and Address Book, and Mail.app also have an amazing amount of power rumbling under the hood. So, in the interest of spreading the love, here's four Mail.app Smart Mailboxes that have been rocking my world over the last months.

tow.com » MsgFiler

Lots of the kids are excited about the arrival of MsgFiler, which is a neat litte app for helping you file away your messages in Mail.app:

MsgFiler is a plug-in for Apple Mail which quickly files emails into existing mailbox folders. MsgFiler’s fast searching means you just have to type a few characters to find the right mailbox. Move selected messages with a click or open a mailbox without having to navigate the mailbox folder pane. MsgFiler is optimized for keyboard-only usage, perfect for Apple Mail power users.

Zesty.

But I'll just play devil's advocate on this one: if you find yourself inordinately excited about the arrival of this (admittedly clever) application, there's an excellent chance that your email archiving system is unnecessarily complex and, in fact, is in need of a major streamlining. Discuss.

The success of yesterday's post on the basics of Smart Playlists makes me think you might enjoy seeing a few more. So, today I want to show you how to get control of a very large iTunes library -- to save space by getting rid of stuff you're not enjoying or listening to, as well as bubble up stuff you may not even realize you like.

If you are an iTunes packrat but feel overwhelmed by your collection (or are simply running out of drive space), try these recipes for Smart Playlists to help you get it together.

I open the floor to all of you on a question of particular personal interest to me: How are you using Mail Tags?

While my uses of it to date have been helpful, I keep getting the feeling I'm not getting all that I can out of it -- especially since the ability to associate Projects, Priorities, etc. to a message could make for some really enticing Smart Folders.

I wonder if my question is ultimately more taxonomic in nature -- ultimately more about Spotlight in general or Tags in very very general: When tagging items on your Mac, what kind '-onomy' are using? How strictly do you enforce your vocabulary? What are the best practices for someone who's new to this?

My usage of Mail Act-On, while far from novel, has revolutionized the speed with which I can blow through email processing.

If you've never seen it before, Mail Act-On is a very clever Mail.app plugin that lets you create key commands that execute Rules you've generated in your Preferences. Sounds pretty dull, right? Absolutely. Until you start putting this stuff into action and learn how painfully slow all that draggy mc drag drag business is. Here's how I've set mine up.

This post is part of the Inbox Zero series.

The truth is that you probably can take the average email inbox -- even a relatively neglected one -- from full to zero in about 20 minutes. It mostly depends on how much you really want to be done with it. The dirty little secret, of course, is that you don't do it by responding to each of those emails but by ruthlessly processing them. Is that how you thought this worked? Answering 500 emails in 20 minutes? Jeez, it's no wonder you're such a mess. Your cognitive dissonance is epic.

Here's the deal: your email has been accumulating because you don't have the time to answer it properly, which is certainly reasonable and accurate. You also fear losing track of the email you haven't responded to -- that it will fall between the cracks. This fear is also reasonable and accurate. But you're just as keenly aware that with the backlog of email you have plus the increasing rate of incoming messages you receive each day, you can't possibly ever catch up. This, sadly, is also entirely reasonable and accurate. It's all reasonable and it's all accurate, but come on: something's gotta give.

Like Kirk's "solution" to the Kobayashi Maru Scenario, there's an easy but non-obvious way to win at this Catch-22: you cheat. You don't answer them all. Not even most of them.

You rewrite the rules. You adapt at a higher level. You have to, or else the Klingons will overwhelm you with their superior fire power and brute force -- and then your email would remain unanswered for eternity. Think how sad that would be.

As my media collection grows and my downloads get larger and more frequent, my poor PowerBook is almost always this close to being completely full. Having an overstuffed drive can hammer your performance as well as take you off-task (“You Startup Disk is almost full…”), so regular deletion of crufty files is a part of most folks' regular Mac maintenance.

Although OmniDiskSweeper is my favorite way to exhaustively comb a drive for fat-assed files, it can be time-consuming on a large drive. So I often do a surgical strike with a few simple Spotlight Smart Folders to identify the most likely candidates for fast deletion. A few very basic suggestions:

Clever way to use Thunderbird’s excellent (semantic) flags to implement at GTD-inspired email triage system

Looks like a good thread in the green to watch and maybe contribute to.