Location-blocking and identity-blocking services that can be commercially offered by a service promoter, e.g., a cellular service provider or a web advertiser. In the identity-blocking service, the service promoter may disclose the current physical location of a mobile subscriber (i.e., a cellular phone...http://www.google.de/patents/US20020077897?utm_source=gb-gplus-sharePatent US20020077897 - Identity blocking service from a web advertiser
