People on motor bikes celebrate American President Barack Obama's visit to Kenya by holding up a photo, center top, of the president and First Lady Michelle Obama in Kisumu, Kenya, Saturday, July 25, 2015. President Barack Obama heralded Africa as a continent “on the move” Saturday as he opened a U.S.-sponsored business summit in Kenya, the East African nation where he has deep family ties. (Photo by AP Photo)

Nuns from the United States dance as they wait for the Holy Mass with Pope Francis (not seen) at the Campus Misericordiae in Brzegi, Poland, 31 July 2016. Today Pope Francis will celebrate the holy mass ending the World Youth Day 2016 in Poland. (Photo by Marcin Obara/EPA)

U.S. Secretary of State John Kerry and Mongolian Foreign Minister Lundeg Purevsuren watch an archer during a Naadam ceremony, a competition which traditionally includes horse racing, Mongolian wrestling and archery, in Ulan Bator, Mongolia, June 5, 2016. (Photo by Saul Loeb/Reuters)

“The Darwin Beer Can Regatta is an event which has been held annually since 1974 in Darwin, Northern Territory, Australia at Mindil Beach. Participants create boats using empty beer cans, soft drink (soda) cans, soft drink bottle and milk cartons. The vessels are not tested for seaworthiness, prior to water events, and those that fall apart are part of the day's entertainment. A great many sundry events go along with the regatta, including concerts, a thong-throwing contest and the "Henley-on-Mindil" competition (named after the Henley-on-Todd Regatta), where participants run their "boats" around like Flintstones cars”. – Wikipedia

Photo: A Darwin Beer Can Boat sails in Darling Harbour on October 31, in Sydney, Australia. Darwin has been named as one of Lonely Planet's top ten cities in the world to visit in it's Best in Travel publication. (Photo by Mark Kolbe/Getty Images for Tourism NT)

Look at the image for long enough and you can make the train change direction simply by thinking about it. Freaky.

Peasants in the re-taken Somme District work in the fields, circa 1916- 1917, in this Library of Congress handout photo. For women 100 years ago, opportunities to work beyond the home and take part in political life were very limited. As the 20th century progressed, hard-won progress included gradually improved voting rights, while the upheaval of war pushed doors ajar as women worked as part of the war effort. U.S. Library of Congress archive photos show women's workplaces ranging from a flour mill in England to a coal mine in Belgium or Lincoln Motor Co.'s welding department in Detroit. International Women's Day is celebrated on March 8. (Photo by Reuters/Bain Collection/Library of Congress)

Natalia Arango works with her mine detector in a zone of landmines planted by rebels groups near Sonson in Antioquia province, November 19, 2015. Women's work takes on a nontraditional meaning for fifteen Colombian women who work to rid the Antioquia Mountains of deadly landmines as the country edges closer to a peace agreement with Marxist rebels to end over a decade of conflict which has claimed 220,000 lives. (Photo by Fredy Builes/Reuters)