Functionally, Coca-Cola's #shareacoke emoji isn't any different from the other custom icons you see on Twitter: if you use the right hashtag, the image shows up in your Tweets. Behind the scenes, however, it represents new potential revenue source for the company. Right now, the campaign is just a test -- but Twitter's Ross Hoffman says the program could expand if it does well. "One of our core values at Twitter is #ShipIt," he told TechCrunch. "The data we get back will help determine the future of what we do with this as a product."

So, will all your future Twitter emoji be tied to advertising dollars? Only time will tell -- but figuring that out is a big deal for Twitter. After all, the company is almost ten years old and it's still not turning a profit. It needs every advertising dollar it can make.

[Image credit: Stuwdamdorp / Alamy]