39. A non-transitory machine-readable storage medium carrying one or more sequences of instructions, which instructions, when executed by one or more processors, cause the one or more processors to carry out the steps of: receiving a message from a message sender; obtaining a reputation score of the message sender, wherein the reputation score of the message sender was determined by performing the steps of: obtaining two or more lists from two or more list providers; determining which lists of the two or more lists indicate the message sender; extracting from each list of the two or more lists indicating the message sender an individual score for the message sender, representing an individual probability that the message sender sent an unsolicited message; computing the reputation score for the message sender from the individual scores for the message sender from each list of the two or more lists indicating the message sender; wherein the step of computing the reputation score comprises determining an aggregate score based on the individual score for each list of the two or more lists by performing at least one of a Chi Squared calculation, a Robinson calculation and a Bayes calculation on the individual scores for the message sender; and when the reputation score is worse than a first predefined threshold, performing a specified action associated with responding to the unsolicited message.
39. A non-transitory machine-readable storage medium carrying one or more sequences of instructions, which instructions, when executed by one or more processors, cause the one or more processors to carry out the steps of: receiving a message from a message sender; obtaining a reputation score of the message sender, wherein the reputation score of the message sender was determined by performing the steps of: obtaining two or more lists from two or more list providers; determining which lists of the two or more lists indicate the message sender; extracting from each list of the two or more lists indicating the message sender an individual score for the message sender, representing an individual probability that the message sender sent an unsolicited message; computing the reputation score for the message sender from the individual scores for the message sender from each list of the two or more lists indicating the message sender; wherein the step of computing the reputation score comprises determining an aggregate score based on the individual score for each list of the two or more lists by performing at least one of a Chi Squared calculation, a Robinson calculation and a Bayes calculation on the individual scores for the message sender; and when the reputation score is worse than a first predefined threshold, performing a specified action associated with responding to the unsolicited message. 43. The machine-readable storage medium of claim 39 , wherein the step of performing the specified action comprises moving the message into a bulk mail message folder.