Game of Thrones is among the most watched programs on television these days, with more than 17.4 million people tuning in for the Season 8 premiere last month -- exceeding the 16.9 million viewers who tuned in for the season seven finale. With a following of that size and the significant buzz surrounding the show and its plot lines, it is arguably one of the most scrutinized programs on television.

Many fans of the show -- which appears on AT&T's (NYSE:T) HBO -- are diehards, watching the program multiple times to glean insight into where the story might be headed. Even the slightest inconsistency is fiercely debated online -- like how characters get from Winterfell to Kings Landing is just one episode, where in previous seasons it took several.

Some eagle-eyed fans spotted what is likely the biggest anachronism in the program yet -- a coffee cup from Starbucks (NASDAQ:SBUX). And that's an even bigger win for coffee purveyor.

One of these things doesn't belong

In the episode that aired on May 5, a coffee cup that appeared to show the familiar Starbucks logo was spotted on a table in Winterfell in front of Daenerys Targaryen, one of the central characters of the show, played by Emilia Clark. This set the internet ablaze. Web denizens were quick to point it out and were left wondering whether it was a production mistake or an intentional and perhaps tongue-in-cheek nod to modern culture.

Bernie Caulfield, the executive producer of Game of Thrones, admitted in an interview with WNYC that it wasn't intentional.

The memes began almost immediately, generating a huge amount of buzz for Starbucks -- and that could be worth a fortune.

Big money

Product placement is big business in Hollywood, with recognizable brands paying huge sums to have their products appear prominently in movies and television programs. HBO, the home of Game of Thrones, doesn't participate in the practice because its customers pay a monthly subscription for the premium cable channel, making the appearance there all the more valuable.

The sheer magnitude of the viewership would dictate a placement fee of at least $250,000 if it were done intentionally, according to Stacy Jones, CEO of Hollywood Branded, a company that specializes in entertainment marketing. 

Then, of course, there's there value of the resulting buzz. Game of Thrones is already a cultural phenomenon, and even those who don't watch it have heard of the show. So what's that type of publicity worth?

"The [public relations] value on this is well over $1 million in word of mouth and how people are actually engaging. Look at all of the memes that are being created," Jones said. "It doesn't even matter whether the brand on that cup is Starbucks or not, because so many people think that it is, and hundreds of thousands of people are already commenting on it, circling [the cup] in the scene [in their screen-capture images], and calling it out. I would say the value for Starbucks on this scale is well into the millions, plural, of dollars."

Some went much, much higher. The president of Apex Marketing Group, Eric Smallwood, said the faux pas was worth more than $11.6 million as of mid-morning, after calculating the value of the social media buzz, television and radio exposure, and digital news coverage. Smallwood expected the coverage to go even higher once the story was picked up on the West Coast and late-night comedy shows.

Getting into the act

Starbucks was quick to get in the act, tweeting its own suggestion about what Daenerys Targaryen would have ordered:

Eventually, even HBO had a little fun at its own expense. The company released a statement saying: "The latte that appeared in the episode was a mistake. Daenerys had ordered an herbal tea."

That's a whole lot of press -- and free publicity -- for one misplaced disposable coffee cup.