1. A method comprising: evaluating, by one or more processors, a plurality of messages, each message associated with an author; logging, by the one or more processors, for each message, information associated with the author, information associated with one or more designated recipients of the message, and time information associated with the message; determining, by the one or more processors, correlation values for one or more sets of the designated recipients based on at least a portion of the logged information; and determining, by the one or more processors, an association amongst a plurality of users over time, the determining being based on the correlation values, at least one of the plurality of users comprising at least one of the designated recipients.