Patent ID: 7895081

Claim:
A computer-implemented method for facilitating transactions between customers of an item transaction system, the method comprising: registering multiple users as customers of the item transaction system; for each of at least some of the customers, automatically identifying items for the customer to make available via the item transaction system, wherein the automatic identifying of the items for the customer includes: retrieving information indicating items previously purchased by the customer from one or more item marketplaces distinct from the item transaction system, and adding at least some of those indicated items to an available item list for the customer, wherein the available item list of the customer indicates items that are available from the customer to be provided to other customers via transactions with the item transaction system; and facilitating item transactions involving customers, wherein the facilitating of the item transactions includes: receiving a request from a customer that is for a first indicated item that is on the available item list of at least one other customer, providing instructions to one of the at least one other customers whose available item list includes the requested first item, wherein the instructions are to send the requested first item to the customer who made the request; receiving requests from one or more customers that are each for a second indicated item that is not currently on the available item list of any other of the customers; and automatically determining to inject additional supply of the second item into the item transaction system based at least in part on demand from customers for the second item exceeding supply of the second item from customers by at least a predetermined threshold, the injecting of the additional supply including acquiring one or more copies of the second item from one or more external sources such that each of at least one of the one or more customers who requested the second item is sent one of the acquired copies of the second item.