• by Loren McDonald , Op-Ed Contributor, October 7, 2010

Email is the most valuable, flexible and successful of all marketing channels. But its success goes well beyond its ability to drive conversions and revenue for companies. Finding that sweet spot remains a challenge for many email marketers, but some have been able to bring out what I called in my  previous column email's "inner Lady Gaga:" an enhanced role that goes beyond the conventional image of being inexpensive and "your father's communication channel."

These marketers have discovered email's power as a retention and loyalty channel. Instead of just filling their subscribers' inboxes with one "free shipping/10 percent off" offer after another, they're adding a slew of emails that surprise, add value or simply engage the recipient.

Following are a few examples from some marketers that exemplify this approach:

Air New Zealand: The UK-region marketing team for the airline has a unique challenge. With only a few flights a day from the UK to Los Angeles and New Zealand, the airline's marketing approach must focus more on brand building and creating word of mouth than attracting frequent fliers.

Besides the usual added content you find in pre-trip emails after a customer books a flight -- local weather and attractions, travel and security tips, etc. -- the email is personalized with a message and photo of the actual fight service manager who will be on your flight.

Online Marketing Manager Chris Sumbler says these emails have been a smashing success with both passengers and the flight crew. Many customers print the email and show it to the crew member. This is my all-time favorite marketing email.

VIE at home: After you order a product such as a cosmetic powder foundation, this UK company sends an email with a link to a video that explains the correct way to apply it.

Education and content like this is one of the biggest trends in marketing.

Also VIE at home: "Can't face the disappointment of another pair of socks?" With this style of copy, Vie at home sends customers an email a month before their birthdays suggesting they set up a wish list.

"All you have to do is set up a wish list, then email it out to your friends and family with a subtle hint." How cool is that?

Peter Glenn: Customers who purchase products made with Gore-tex from this sporting goods retailer receive an email with detailed care instructions.

I never read the instructions that come with things I've purchased. However, an email like this will always be in my inbox when I need it.

Fabric.com: This online fabrics retailer notifies customers who have previously requested fabric swatches that those fabrics could go out of stock soon. While this drives increased purchases, the notification can be a very helpful prompt to someone who forgot or procrastinated about buying the fabric. ShoeBuy: This shoe retailer applies a twist to the standard one-year purchase anniversary email. It adds information on the specific product the customer bought previously ("Your size and color is still available") and encourages repurchasing by linking directly to the products on its site.

If you loved those slinky red pumps, this reminder makes it easy to buy another pair.

OpenTable: As a male who tends to forget birthdays, anniversaries and other occasions my wife deems important, I appreciate OpenTable's last-minute Valentine's Day restaurant reminder.

Sent out shortly before Feb. 14, the email reads: "With OpenTable, you still have enough time to pull off a spectacular night for your sweetheart.... Sure you got a late start, but with our vast list of restaurants, there are premier tables to be had Valentine's weekend."

This kind of email not only adds value but also probably saves a few marriages.

LG: LG reminds purchasers of its premium water filtering system to change the filter every six months. The email includes the purchase date, model and serial numbers and a link to a list of authorized retailers and distributors where the customer can buy the filter.

This is simply good business. If the system stops working properly because I didn't change the filter, I'm more likely to blame LG, not myself.

Have you saved any examples of emails that add value to the recipient beyond just promotional content, or do you know of any? Please share a description in the comments section below.

Until next time, take it up a notch.