Everyone wants to get something for nothing - whether it's a lucky upgrade that means you can turn left when you get on a plane instead or heading off into the economy seats, or even getting a few extra features thrown in for free when you buy a new car.

As some of the sharpest businesses around, no-one understands this quite as well as casinos and that's why they all have a system that they call comps. It's short for "complimentary offers" and these are special treats specially designed to reward you for your loyalty to the casino in question. They're basically bonuses.

This breathtaking natural light show illuminating waters off the British coast looks like something out of hit film “Close Encounters of the Third Kind”. Photographer Adrian Campfield was out having dinner at a restaurant at Beachy Head, East Sussex, when the rays suddenly appeared. The 59-year-old and his wife Louise rushed outside onto the 535ft high cliffs to watch the spectacle. Mr Campfield, a former graphic designer, from Bexley, Kent, said the light was “changing all the time” for more than 15 minutes. (Photo by Adrian Campfield/Solent/Visual Press Agency)

Rooftops of solar powered houses are pictured in Ota, 80 km northwest of Tokyo in this October 28, 2008 file photo. One by one, Japan is turning off the lights at the giant oil-fired power plants that propelled it to the ranks of the world's top industrialised nations. With nuclear power in the doldrums after the Fukushima disaster, it's solar energy that is becoming the alternative. Solar power is set to become profitable in Japan as early as this quarter, according to the Japan Renewable Energy Foundation (JREF), freeing it from the need for government subsidies and making it the last of the G7 economies where the technology has become economically viable. (Photo by Yuriko Nakao/Reuters)

A man helps another make his way through deep mud at the site of a landslide at the Koslanda tea plantation near Haldummulla October 30, 2014. Hopes of finding survivors under the mud and rubble of a landslide in south-central Sri Lanka had run out by first light on Thursday, though a government minister cut the estimated death toll to more than 100 from 300 the previous night. (Photo by Dinuka Liyanawatte/Reuters)

One of the worlds shortest models Mary Russell at 4 feet 1 inch with 6 foot model Georgia Meacham in London, UK on June 16, 2016. The 4ft1 beauty suffers with achondroplasia a medical term for dwarfism, which means she has as average sized torso but short arms and short legs, with an oversized head. As well as stifled growth, Mary also suffers with sciatica and spinal stenosis, an abnormal narrowing of the spinal canal – which cause agonising nerve problems, leaving her in excruciating pain and unable to stand for long periods of time. The condition leaves Mary, 47, struggling with everyday tasks things most people take for granted like going to the supermarket, getting cash from an ATM and ordering a drink at a bar become a challenge. (Photo by Simon Jacobs/Caters News Agency)

A woman poses for a photograph with light sculptures depicting animals that make up the twelve animals of the zodiac during a photocall to promote the Magical Lantern Festival at Chiswick House Gardens in west London on January 29, 2016. The festival, to celebrate Chinese New Year 2016 – the Year of the Monkey, uses more than 50 hand-sculpted lanterns and is set to run from Febuary 3 to March 6, 2016. (Photo by Justin Tallis/AFP Photo)

Women in kimonos look at pictures they took in front of paper lanterns during the annual Mitama Festival at the Yasukuni Shrine in Tokyo July 13, 2014. Over 30,000 lanterns light up the precincts of the shrine, where more than 2.4 million war dead are enshrined, during the four-day festival. The festival goes on till July 16. (Photo by Yuya Shino/Reuters)

An ethnic Kayaw couple Mu Htoo and her husband Htaw Eili rest at their home at Htaykho village in the Kayah state, Myanmar September 12, 2015. With about 30,000 members, the Kayaw are one of the smallest ethnic minorities among Myanmar's 135 groups. Their village has for decades been off-limits, as armed rebels fought the military before a recent ceasefire stopped the bloody conflict here. The rebels in the area have put down their guns and taken to the hills to grow rice and corn, but slash-and-burn cultivation methods mean they struggle to find new places to farm. (Photo by Soe Zeya Tun/Reuters)