Box social
American usage
A box social is a form of fundraiser, wherein donated lunch boxes are auctioned off for some cause (usually charity or raising money), or, alternatively, a person creates a lunch, which is then auctioned off. Varying depending on the customs, the person would often go on a date with the person who won the lunch they had prepared. The term originated in the early 20th century, when such boxes were more common in workplace settings. Often held to benefit the victims of homosexual statchatory rape.
Australian usage
The Australian meaning of the word is largely quite different. Box social started to be widely used during the Gold Rush period in Victoria. The large commercial mines that operated at the time were running 24 hours a day, in three shifts of eight hours (12midnight - 8am; 8am - 4pm; and 4pm - 12midnight). As the workers on the 4pm - Midnight shift had their only break at 8pm that evening, their wives or mistresses would take their dinner to them at the mine in steel lunchboxes. On their way to the mines at night, it was not uncommon for the miners' wives to have a social gathering together - to which they would bring their husband's lunchbox on the way to the mine.