Methods and systems of establishing a network-based system for purchase and sale of at least one of an option contract and a futures contract to acquire an item or to attend an event, wherein the contract is exercisable upon the occurrence of a contingency. The contingency may relate to the presence of a particular team in a game and the location of the game. In some instances, the contingency may relate to the position of a participant in the event in the standings at a time proximate to the occurrence of the event.