The sky's the limit when it comes to quenching one's thirst for a pint of beer - at least for those in South Africa attending an annual outdoor music festival.

Festival goers rocking out at Oppikoppi this week had the opportunity to skip out on the long lines that typically crowd a beer tent and have their drinks delivered via a flying drone that hovered 15 metres above their heads.

Carel Hoffman, the festival's director, said thirsty patrons placed their orders using a smartphone app which then registered the customer's position using the GPS satellite chip on their phone.

"The delivery guys have a calibrated delivery drone. They send it to the GPS position and drops it with a parachute," said Hoffman on a farm in the country's northern Limpopo province.

The drone - nicknamed "Manna" from the biblical story in which God provides the Israelites with an edible substance dropped from the sky - was built in South Africa.

The novel idea is another example of drones - unmanned aerial vehicles that can be operated independently or using a remote control - being hijacked by private citizens to make civilian life a little bit easier.

While the word drone typically conjures up images of tactical military strikes, their smaller and "friendlier" relatives have been slowly making their way into our everyday lives.

According to an estimate from the U.S. Federal Aviation Administration, about 7,500 civilian drones will be in use within the next five years, performing a number of useful, and sometimes strange, functions.

From replacing servers at restaurants, to monitoring crops, drones are perhaps the way of the future, making mundane tasks a little less boring.

Here's a list of five high-flying tasks that are being performed by drones:

1. Spud spying

Researchers at Oregon State University have come up with a fresh way to monitor how potato crops are doing, using a pair of battery-powered drones that weigh only a couple of pounds, to detect unhealthy plants.

The drones, named HawkEye and delta-winged Unicorn, are outfitted with small infrared cameras that can detect imperfections that are typically invisible to a farmer's eye.

"When plants aren't happy, they look different, but not necessarily to our eyes," Phil Hamm, director of the Oregon State extension centre at Hermison, told The Associated Press. "We want to recognize plants that aren't happy before there's a reduction in yield."

Although gusty winds can be a problem for takeoff, Boeing Research & Technology - the company that is leasing the drones to Oregon State - says the drones can fly over an entire 125-acre crop in approximately 15 minutes.

2. Weather gazing

Located in the heart of Tornado Alley, researchers at Oklahoma State University are designing and building a futuristic Kevlar-reinforced drone to fly directly into the eye of a storm, sending back real-time information to first responders and forecasters.

The upgraded weather balloon -- which weighs less than 23 kilograms -- is controlled using a laptop or iPad and could be operational in roughly five years.

"Technology has really been catching up to what we wanted to do," Jamey Jacob, a mechanical and aerospace engineering professor at OSU told The Associated Press.

Similar technology could be used in the future to monitor wildfires, relaying information to firefighters so they don't get trapped by fast-moving flames. 

3. Food ferrying

More than just a barmaid, drones are also being developed to deliver food, eliminating the need to perhaps leave a tip at the end of a meal.

YO! Sushi, a restaurant in the U.K., is testing a flying waiter made of light-weight carbon fibre that's powered using four propellers.

"(The drone) is a high-tech flying platter custom built using the most advanced RC Drone quadicopter technology and is remote controlled through an on-board Wi-Fi system and iPad software," explains a blog post on the restaurant's website.

In a YouTube video posted by the restaurant, the drone - nicknamed the "iTray" - is seen flying serenely to customers while carrying a tray full of food. But whether or not the video lives up to its expectations is another story.

According to a review in The Guardian, the iTray, which is being tested out at the chain's Soho location, was less than graceful.

"(The drone) drunkenly lurches around at knee height, crashing into camera tripods and chairs or just the ground, as the pilot mutters darkly about the wind factor and low batteries," the writer says.

The chain hopes to work out all the kinks by next year when the iTray is set be used all their U.K. locations.

4. Pizza delivery drone

Upping the ante, Domino's Pizza in the U.K hired engineering company AeroSight and creative agency T + Biscuits to test out the feasibility of drones delivering hot pizzas.

Branded as the DomiCopter, the current prototype can be seen in a YouTube video where viewers are taken along for a ride as the pizza-clutching drone soars easily through the sky, travelling over waterways and city streets to deliver two pies to a hungry customer outside his front door.

5. Flying photography

Based in the U.K., WhisperDrone is giving traditional landscape photography a whole other meaning.

Clients of the aerial photography firm can capture jaw-dropping pictures from up to 400 feet above the ground using a drone piloted by Marcus Keegan, a "photographer" who started his aviation career with the Army Air Corp in 1976, according to the company's website.

With files from RelaxNews and The Associated Press