The City of Sydney has recently installed two 'Reverse Vending Machines' in the central city area. The machines are part of a trial in which the user is offered one of two rewards for inserting empty beverage containers such as aluminium cans and plastic bottles. Essentially a Cash for Containers scheme, users can receive prizes such as food vouchers, bus passes or donate their winnings to Clean Up Australia which promotes having Cash for Containers schemes everywhere. In the short time they've been operational over 5million containers have been collected by the machines!