It may be hard to get water from a stone or blood from a turnip, but Coca-Cola says it can get Coke Zero from a billboard.

The Atlanta-based beverage maker will debut "drinkable advertising" this weekend during the NCAA Men's Final Four in Indianapolis. A 26-by-36-foot billboard with tubing that spells out "Taste It" will dispense free samples of Coke Zero, the company's zero-calorie soft drink.

The billboard will be at the March Madness Music Festival in White River State Park.

Coke isn’t saying much about the technology behind the billboard, only that the “billboard appears to magically dispense ice-cold Coke Zero from a massive contour bottle through 4,500 feet of straw tubing.”

Coke Zero, like other carbonated sodas, is facing challenges in growing market share as health-conscious consumers seek out alternatives to sugary drinks. Last year was the 10th in a row for a decline in consumption of soft drinks, according to research by Beverage Digest. While Coca-Cola’s flagship brand gained market share last year, Coke Zero lost ground.

The concept of a drinkable billboard is already a reality in Peru. The University of Engineering and Technology in Lima has constructed a billboard that literally captures the humidity (which averages 83% in Lima) and converts it into drinkable water. Times magazine reported in 2013 that the billboard features an inverse osmosis filtration system. The water then passes through small ducts to a holding tank that has a faucet. The billboard produced about 26 gallons of water a day.

“The Drinkable Book,” produced by DDB New York and the Water is Life charity, is a manual of safe water tips with pages that are coated with silver particles. The pages can be used to filter water and kill water-borne diseases like cholera, E. coli and typhoid.

The drinkable advertising campaign for Coke Zero includes commercials during the semifinal games Saturday on TBS and the national championship game Monday on CBS. During the commercials people who have the Shazam app will see Coke Zero poured on TV while a glass fills on their mobile device. Once the glass is full, a mobile coupon is provided for a free 20-ounce bottle of the drink.