Operating on-line marketplaces for sellers and buyers of goods and/or services; Providing a website featuring an online marketplace for exchanging goods and services with other users; Provision of an on-line marketplace for buyers and sellers of used and returned goods.; Provision of an online marketplace for buyers and sellers of goods and services; The bringing together, for the benefit of others, of a variety of goods and services, enabling customers to conveniently view and purchase those goods and services from an Internet web site particularly specializing in the marketing of the sale of goods and services of others