1. A method for generating signals from distributed data sources controlled by a multiplicity of owners for selling in a signal marketplace, the method steps comprising: providing at least one signal from a first data source and at least one signal from a second data source; wherein the signals originate from different distributed data sources controlled by different owners and the signals are indexed in a centralized database and each of the signals is automatically assigned a value in the centralized database and associated with its corresponding indexed signal; and wherein the value is automatically generated by a remote server computer associated with the central database, based upon at least two factors associated with the value.