You've made it. We've made it. We're all here - the end of the year is upon us, with the incredible week between Christmas and the New Year celebrations just around the corner. That week always seems to transcend space and time, where questions like "where am I?" start to become "who am I?" and even "why am I?" depending on how the Christmas parties went.

Regardless of your reason for celebrating at this time of year, practically everyone does it. We therefore wish you the happiest of holidays as we bring you the final edition of Ghost Mail Weekender for 2024.

Speaking of Christmas, when 8-year-old Dillon Helbig finished writing and illustrating his first book, he knew that it was so good that others should get a chance to read it too. But since he didn’t have a publisher or an agent, he had to take matters into his own hands. Thinking quickly, Dillon smuggled his book, The Adventures of Dillon Helbig's Crismis (by “Dillon His Self”), into his local library in Boise, Idaho, and slid it onto the children’s shelf. “I’ve been wanting to put a book in the library since I was five,” Dillon shared, noting he had to sneak past a few librarians to pull it off. Once Dillon’s parents found out about his scheme, they hurriedly phoned the library, fearing that the book had been discovered and discarded. But instead, the opposite had occurred. The librarians had found Dillon’s book on the shelf and loved it so much that they officially added it to circulation. Now, the book has a 56-person waitlist that could take at least four years to clear. As library manager Alex Hartman put it, “If there’s ever a safe place for a book, it’s here.”

Bravo, Dillon - an author and a legend! As the famous and important quote by Steve Jobs goes: "Real artists ship!"

Taking a well-deserved break this week from shipping her column, Dominique Olivier's Fast Facts section is instead a look back at some of the most popular column articles of the year. From sideways cruise ships to very black paints and even whispers of the Italian agromafia, there’s enough material in here to liven up even the driest family lunch table conversation this Dezemba.

As for who Fat Kathy is - well, you'll just have to read on for this week's juicy Weekender story.

See you in 2025!

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TL;DR: In Warsaw, Poland, eight clams have the power to switch off the entire city’s water supply - but only if the majority of them agree that it needs to be done.

Fat Kathy’s clams may sound like the lunch special at your local dive bar (or a punk rock band name insinuating something filthy), but in reality, this is Warsaw’s way of making sure the water stays clean. Gruba Kaska (affectionately known as “Fat Kathy”) is a water pump and somewhat of a local landmark in Warsaw. The pump sits at the end of a slimy, 300-metre tunnel under the Vistula River. And guess what you’ll find inside the pump station? Eight clams plugged into computers, monitoring the quality of the city’s drinking water.

It sounds like a medieval practice, but it doesn’t get more modern than this. Warsaw’s water supply relies on a tag team of tech and biology. Artificial sensors are also in use, but it’s the mussels - nature’s original bioindicators - that bring their A-game, sniffing out overall water toxicity with pinpoint precision.

This isn’t just a Warsaw thing either. Over in Poznań, where the city’s water comes from the Warta River (some Polish names are clearly easier for tourists to interpret), mussels are also leading the charge. The Warta flows through some of Poland’s most crowded cities and oldest industrial zones. This creates opportunities for heavy metals like chromium to sneak into the water, making it a less-than-ideal cocktail for human consumption.

So, what are the clams doing about it? Well, these little divas only thrive in pristine, oxygen-rich waters, so they’re sensitive to the tiniest changes in quality. When everything’s clean and fresh, they filter-feed with their shells wide open, living their best lives. But as soon as the water turns sketchy - BAM. They snap those shells shut.

In Poznań, scientists from Adam Mickiewicz University gave these mollusks a high-tech makeover by hot-gluing a combination of springs and magnets to their shells. When the clams open or close, the magnetic field shifts, and computers pick up the signal. If one or two clams shut, a warning will be issued but no action will be taken without a human being involved. If four of them close at once, the system shuts down the water supply automatically. No debates. No delays. Just mussel-powered engineering brilliance.

50 Polish waterworks plus one in Russia are using the same clam-based system to monitor water quality. Of course, there are a few quirks. Clams, bless them, aren’t exactly chatty. They’ll clam up when something’s off but won’t spill the beans on what toxin is causing the issue. And while they’re great at sniffing out heavy metals and pesticides, they’re not as sharp when it comes to spotting sneaky pharmaceuticals.

Still, Piotr Klimaszyk, who heads the team behind this clever system, is all in. “It’s cheap,” he says. “Just clams, magnets and computers. You can check water quality hour by hour, minute by minute - so, why not?”

Exactly, Piotr. Why not?

This week, it's a throwback to some of your favourites of the year

• In the year of the Olympic Games and that opening ceremony, Dominique took us back to the Men's Marathon at the 1904 event. Suffice to say that things have changed and are a lot less dangerous.

• With a great love of art, it's little surprise that the story of Vantablack was on Dominique's radar this year. Get ready to learn about the blackest black around - and the pinkest pink! 

• Anyone who has built a business already knows that succession planning is extremely difficult. Family businesses are even trickier. So, how on earth has famous cymbal maker Zildjian gotten it right for 400 years?

• Sometimes, you read a story about a disaster. Then, you read the sequence of events leading up to it and they just shock you from start to finish. The Costa Concordia is practically peerless when it comes to a comedy of errors that ended in tragedy. AI might not be perfect yet, but it's hard to imagine how it could've done any worse than Captain Francesco Schettino.

• From awful ship captains to the agromafia, Italy never ceases to dish up a juicy story. Saving the best for last, the most popular column article this year by a country mile was Dominique's piece on why gangsters choose olives over cocaine. Buckle up for some liquid gold!