Since 1971, Casinos Austria have commemorated big events by manufacturing 'Special Issue' chips where 20% of earnings from the face value of each chip is donated to charitable, cultural and athletic games (e.g. the 1976 Olympic Games, the International Year of the Child in 1979 and World Wildlife Fund...)

http://www.themogh.org/cg_chip2.php?id=atwic1&sort=type