A system that allows individuals to maintain lists of items of interest in an account, such as books, restaurants, hotels, clothes, etc. The system allows an individual to share an item in a list with another individual. When an individual wishes to share an item, the system may generate a share message to be sent by a selected method to a recipient. The share message may include a link for allowing the recipient to view the item on the system and provide a mechanism for allowing the recipient to accept or decline the share. The acceptance or, in particular, the rejection of the share establishes a positive or negative relationship between each individual and the item. The sharing of Items between individuals can be temporally and geographically mapped to identify patterns of interest, the value of an item to one or more people, or the strength of the bond between two or more people.