Starbucks (SBUX -2.43%) is getting a lot of press recently. From launching its first redesigned Teavana store last week in New York City to rolling out La Boulange food products in thousands of U.S. Starbucks locations, the world's biggest coffee retailer is firing on all cylinders. Today, the chain announced a new e-commerce initiative called Tweet-a-coffee. That's right: Starbucks' packed agenda now includes selling virtual goods via Twitter.

Here's how it works.

Coffee + Twitter
Starbucks and Twitter are testing a new gifting platform that lets customers go to starbucks.com/tweet-a-coffee and send a $5 Starbucks eGift card to a friend on Twitter. You'll need to create a Starbucks account if you don't already have one. Once your Starbucks and Twitter accounts are linked, simply include the following three things in a tweet: @tweetacoffee, "to", and the recipient's Twitter handle.

This could be particularly helpful for Twitter as the social media site kicks off the road show for its upcoming initial public offering. The microblogging service is set to debut on Nov. 7 on the New York Stock Exchange, and will trade under the ticker symbol: TWTR. Twitter's new partnership with Starbucks highlights the potential for Twitter to generate revenue outside of advertising and "promoted tweets."

Starbucks' Tweet-a-coffee program demonstrates Twitter's evolution as an e-commerce platform. With more than 230 million active users per month, Twitter shouldn't have any trouble convincing more companies to follow in Starbucks' footsteps.

In fact, American Express (AXP -0.74%) took a stab at social commerce earlier this year when it teamed up with Twitter to let Amex members make purchases on Twitter using specific hashtags. Similar to the new Starbucks offering, American Express cardholders must first sync their accounts with Twitter before using the service.

In addition to the credibility boost, these partnerships also give Twitter a new avenue for collecting data about the way its users leverage the Twitter platform to make purchases and interact with brands. Perhaps we'll get more insight into Starbucks' new partnership when the company reports earnings on Wednesday. For now, it's clear that Twitter's potential continues to grow by the day.