Apple just continues to do cool stuff. The other day I was at my local Apple retail store buying a (ridiculously overpriced) case for my iPhone. Its checkout process is nifty. I was most impressed when the "genius" behind the counter hit me with a question I'd never heard before: "Would you like your receipt printed or emailed?" I was a little bit stunned, since I'd never had to consider this option before. But it didn't take me long to figure out my preference: "Emailed please." Apple already had my email address paired with my credit card (presumably through my iTunes account), so all it had to do was confirm my email address and voila–receipt sent.

Like the curious gadget-carrier that I am, I was able to check that email account on my iPhone as I was leaving the store, and sure enough ... the receipt was in my inbox. Awesome!

This transactional email offering is great in so many ways it's hard to list all of the benefits, but here are a few:

• For Me: I get a receipt, but I don't have to stuff it in my pocket, wallet or the bag. I can wait 'till I get home to my computer and organize it, ignore it forever or just search for it if I ever need it for any reason.
• For Apple: reduced paper cost, increased coolness, increased green-ness and one more way to amaze (and engage) customers with its innovativeness.
• For Mother Earth: fewer trees sacrificed for paper receipts.

Yet as cool as Apple is, there's still room to do it better. Why not take advantage of the fact that transactional messages can include some promotional content? When Apple sends the receipt for my iPhone case, it should include a coupon for some cutting-edge earbuds or a cool new application in the app store. Since transactional emails are the most likely type to be opened, why not take advantage of that captive audience and show them something else they might be interested in? A number of Silverpop clients send branded Transactional emails that entice shoppers back.

In the end, though, it's a big success for Apple. Color me impressed and thoroughly engaged thanks to Apple's cutting-edge use of transactional email.