A search engine receives query terms from a client. In response, the search engine executes a search on a web directory to identify zero or more documents that match the query terms. The identified documents are associated with one or more categories. The search engine probabilistically selects one of the categories associated with the identified documents. Each message in a message database is also associated with one or more of the categories. The search engine accesses the message database and selects at least one message associated with the selected category. The search engine returns a web page containing references to the documents matching the query terms and the one or more messages selected from the message database to the client.