Small transportation boats, known as bumboats, leave trails of light as they travel across Marina Bay past the skyline of Singapore in this photo taken in 2004. Singapore holds a Jubilee weekend from 7 to 10 August to celebrate the 50th anniversary of its independence. Fifty years ago, hundreds of small boats lined the Singapore river in the city centre. Today, most small boats are gone, except a handful of neon-lit tourist ferries. Maritime trade is still the backbone of the city-state but after decades of rapid growth Singapore, which at less than half the size of London is among the world’s most densely populated nations, is also a popular tourist destination and a thriving global financial hub. (Photo by Edgar Su/Reuters)

In this March 21, 2015 photo, 15-year-old Guerline Augustin carries river water on her head, back to a borderland encampment outside the southeast Haitian town of Anse-a-Pitres, Haiti. The encampment is filled with people who either fled or were forcibly removed from the neighboring Dominican Republic amid an immigration crackdown. Within the next month, authorities hope to move nearly 2,400 people out of six encampments by providing subsidies for them to rent homes for a year in southeastern Haiti. The International Organization for Migration is coordinating the effort with $2 million from a U.N. emergency fund. (Photo by David McFadden/AP Photo)

In this March 12, 2015 photo, a man tours a graffiti exhibition at the Museum of Modern Art, in Bogota, Colombia. The city-run museum recently held an exhibition highlighting the work of Bogota street artists who go by aliases such as Joems and the MonsTruacioN collective. (Photo by Fernando Vergara/AP Photo)

London Mayor Boris Johnson takes part in a tug of war with members of the armed services to launch the London Poppy Day, outside City Hall, in London, October 27, 2015. London Poppy Day is a street collection event to raise money for serving and retired members of the armed services and their families. (Photo by Stefan Wermuth/Reuters)

1: Dubai's Burj Khalifa is the tallest building in the world, but perhaps not for long. Saudi Arabia has announced plans to build a 1 kilometer (3,280 foot) tower into the sky, to be named the Jeddah Tower, scheduled for completion in 2020. The Burj Khallifa currently stands at 2,716 ft. (Photo by Matthias Seifert/Reuters)

#1: Superman. According to McAfee, 16.50% of Web searches for Superman led to sites with viruses and other malicious software. Pictured here: The Superman costume that was worn by Christopher Reeve in “Superman: The Movie” on display at Profiles In History in Calabasas, northwest of downtown Los Angeles, on July 19, 2012 in California. (Photo by Frederic J. Brown/AFP Photo)

A Brussels Airlines aircraft prepares for landing in Cointrin airport during sunrise over the Mont Blanc in Geneva December 1, 2011. (Photo by Denis Balibouse/Reuters)

Rag pickers collect recyclable material at a garbage dump in New Delhi November 19, 2014. (Photo by Ahmad Masood/Reuters)