20th March is celebrated as World Happiness Day, and it's remarkable to know the lengths to which people go to make themselves happy. A Chinese community is enabling people to 'buy happiness' online. Formed by common people, the "praise groups", known as kua kua groups, are for those who wish to receive compliments or want to be paid for giving one. The groups are particularly popular among college students who are seeking flattery or affirmation and is the latest fad on apps such as WeChat and QQ. Netizens can purchase a compliment for as low as $1!