A prototype Rollkers transportation device is displayed during a press event at the Mandalay Bay Convention Center for the 2015 International CES on January 4, 2015 in Las Vegas, Nevada. The product is not a skate; it balances for you and when you place it on the bottom of your shoe, it gives you the ability for faster transportation based on walking. The balance CES, the world's largest annual consumer technology trade show, runs from January 6-9 and is expected to feature 3,600 exhibitors showing off their latest products and services to about 150,000 attendees. (Photo by Ethan Miller/Getty Images)

Yang Juan, an employee at Goopal Group, takes a nap in her seat after lunch, in Beijing, China, April 21, 2016. Office workers sleeping on the job is a common sight in China, where a surplus of cheap labour can lead to downtime at work. But in China's technology sector, where business is growing faster than many start-up firms can hire new staff, workers burn the midnight oil to meet deadlines and compete with their rivals. Some companies provide sleeping areas and beds for workers to rest during late nights. (Photo by Jason Lee/Reuters)

People view artist David Byrne's installation "Tight Spot" beneath Manhattan's High Line park on September 27, 2011 in New York City. The 48-foot by 20-foot inflatable globe is squeezed beneath the steel support framework of the High Line and is accompanied with a rumbling audio soundtrack created by distorting Byrne's voice. (Photo by Mario Tama/Getty Images)

In preparation for the Dubai Duty Free Men's Open, Andre Agassi and Roger Federer of Switzerland, couldn't resist the temptation to have a friendly “hit” on the world's most unique tennis court, the Helipad of the Burj Al Arab, the world's most luxurious hotel. Standing 321 metres high on a man made island, the majestic Burj Al Arab is without doubt the most recognizable hotel in the world. The hotel's helipad, which is situated 211 metres high covers a surface area of 415 square metres. The pictures were taken on February 22, 2005, in Dubai, United Arab Emirates. (Photo by Getty Images for Dubai Duty Free)

These adrenaline-junkie climbers go to extraordinary lengths, and heights, to take a selfie. Hundreds of metres above the ground, the climbers risk their life and liberty as they scale huge structures and photograph the results. Known as urban exploration, the aim is to find extremely high and almost inaccessible city buildings and reach their dizzying summits. (Photo by Yaroslav Segeda/Solent News)

Denver Broncos cheerleaders during the third quarter. The Denver Broncos played the Kansas City Chiefs at Sports Authority Field at Mile High in Denver, Colo. on September 14, 2014. (Photo by Aaron Ontiveroz/The Denver Post via Getty Images)

The beautiful shots were taken by photographer Amos Chapple using a camera mounted to a quadcopter drone. This enabled him to capture these unusual aerials showing some of Europe’s sights like they’ve never been seen before. Travelling across the continent he took photos everywhere from France and Germany to Spain and Russia. Photo: Clouds swirl through the pillars of Sagrat Cor Church, high on a hill above Barcelona, Spain. (Photo by Amos Chapple/Rex Features)

China’s new tallest building has received unexpected publicity thanks to Russian free climbers Vadim Makhorov and Vitaly Raskalov. The pair took two hours to climb 650 metres up the unfinished Shanghai Tower. They did not use safety equipment on their ascent to the top of a crane attached to the tower, from where they took these extraordinary pictures of Shanghai. Photo: Vitaly Raskalov's feet dangle from the top of the Shanghai Tower, high above the Shanghai World Financial Centre. (Photo by Vitaly Raskalov/Caters News Agency)