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.

Micro pigs have become so popular in England that they are almost impossible to get hold of. They are going for as much as $1,1000 apiece. (Photo by Geoff Robinson)

India: A sweeper cleans the side of a road near a replica of the Eiffel Tower amid heavy fog in the early morning in the northern Indian city of Chandigarh January 18, 2010. (Photo by Ajay Verma/Reuters)

“A prototype lunar lander was destroyed on August 9, 2012, at Kennedy Space Center during its first free flight”. – James Dean via Florida Today

Photo: Morpheus Ground Level Hot Fire. Photo Date: April 2nd 2012. Location: VTB Flight Complex; Photographer: Joe Bibby

A SpaceX Falcon 9 rocket lifts off in Florida on Saturday, October 21, 2023. The rocket is carrying 23 Starlink satellites. (Photo by Malcolm Denemark/AP Photo)

A selection of work by four photojournalists who have won grants of $10,000 and editorial support from the agency. Here: “Chasing Winter” by Katie Orlinksy. In late summer and early autumn polar bears flock to the native village of Kaktovik in the Alaskan Arctic to eat at “the boneyard” – the remains of whales annually hunted by the community. (Photo by Katie Orlinsky/Getty Images)

In this photo taken on March 16, 2019, 13-year-old Reymark Cavesirano collects left over herring onboard a fishing boat anchored at the mouth of Manila Bay off Navotas City in suburban Manila. Cavesirano, a grade five student, paddles to the anchored fishing boats and helps crew clean their nets, and in exchange collects leftover herring still tangled in the nets. Across the Philippines, there are 5 million child labourers, aged between five and 17, many of them working in dangerous conditions. About 22 million people – a fifth of the population – live below the national poverty line. (Photo by Ted Aljibe/AFP Photo)