Email is my main productivity tool. When you receive several hundred emails a day, processing these incoming messages quickly becomes a mission critical task! Being an advocate of Getting Thing Done, I’ve come to use the following techniques to process email.
1) Use Today, Later, Home, and Waiting For Categories
I make extensive use of Categories to classify and sort email. My Inbox Categories:
Incoming Email (no category)
When an email comes in by default it either has no category and the text is ‘Black’. When I see these emails I know that I have not processed these emails yet, and they need attention.
Today
When I scan the email and decide that the email must be responded to or acted on Today, I set its category to Today. It has its own special color. In Entourage (Microsoft’s Mac Outlook-like Email Client) I set up a script so that simply hitting Ctrl-T sets the selected emails to this category.
Later
If the email requires action on my part, but the email can wait till tomorrow or later, I set its category to Later. Later emails can wait till a future date, but as time permits I might address them today. It has its own special color and Ctrl-L sets the selected emails to this category.
Home
If the email is something I want to respond to when I get home that evening, or if it’s an email I need to show or review with someone in my family, I set its category toHome. It has its own special color and Ctrl-H sets the selected emails to this category.
Waiting For
If I respond to an email but I need to get a response, or if it’s simply an email in a thread I need to ‘watch’ and see through the topic till resolution, I set its category toWaiting For. It has its own special color and Ctrl-W sets the selected emails to this category.
2) Managing Your Inbox — The Daily Review
Every morning I sort my email into the above categories. I read the Later emails and may flag some of them as Today. I read the Waiting For emails and if necessary send out a reminder to those from whom I need a reply. Then over the course of the day as emails come in I process emails into the appropriate categories.
3) Project Folders
Sometimes multiple emails on the same topic start to fill up my inbox. Rather than store dozens or hundreds of emails clutter my inbox, I create a project folder. I have a main Project folder, and underneath it create a subfolder for any multi-email project or topic. I put emails in this project folder, and ones that are archived I flag asDone (Ctrl-D). I have a note on my separately maintained ‘Goals’ document (a daily tasks master list) and have a note to work on that project, then go to the project folder at some point in the day to deal with the multiple emails that I have collected on the topic. The Done category helps me separate archived emails from active emails that need attention.
4) Remember the Two Minute Rule
An important Getting Things Done principle is any task that you run across that takes two minutes or less is done immediately. So when you read emails that fill this description, deal with them at once. Otherwise you’ll scan the email multiple times a day, and a 1.5 minute email response ends up take 4 minutes of your day. With dozens of emails being processed inefficiently, those lost seconds add up!
Take a look at Apple's latest invention. 360-degree scrolling. A great boon for graphic artists. Here's the description: 
Some great charts for 'Getting Things Done' advocates: