1. A computer-implemented method, comprising: maintaining a first queue of a first user in computer storage, said first queue identifying a plurality of items selected by the first user from an electronic catalog of items; maintaining a second queue of a second user in computer storage, said second queue identifying a plurality of items selected by the second user from the electronic catalog of items; detecting that the first and second users share a common delivery address; in response to detecting that the first and second users share a common physical address, generating a user interface having a hyperlink that provides an option to the first user to have the first and second queues used in combination to select items for delivery to the first user, and providing the user interface over a computer network to a computing device of the first user; creating an association between the first and second queues at least partly in response to acceptance of the option by the first user; reordering the plurality of items specified in the first queue for the first user based, at least in part, on the plurality of items in the second queue, such that the second queue is taken into consideration in re-ordering the plurality of items for the first user, said reordering comprising increasing a ranking of a first item in the first queue, via execution of program code by physical computer system, based on the association between the first and second queues; and controlling delivery of the plurality of items to the first user such that the items are delivered in an order that is based on the reordering; said method performed by a computer system under control of program instructions.