From Lexicanum

Although the number of free roaming rangers is unknown, the Aliatoc have been known to send off requests for free-lance rangers of their craftworld in times of need. It is believed to be a psychic message sent out by the craftworlds leading Farseer through the Webway.

The above needs to be cited. --Rlyehable 02:51, 18 June 2007 (CEST)