A method includes computing a cross-spectral surface of a signal. For that purpose, the evaporator device uses a vapor permeable membrane as the element responsible for causing the evaporation of the product to be evaporated. An up-vector is automatically detected at each of a plurality of centerline points of the rib centerline of the at least one rib. In a further aspect of the present invention, the wireless device may also pre-fetch contents from the identified web sites in times when bandwidth is not in use to further speed responsiveness of the device. The condenser may be mounted within the chimney and may use cold seawater as a coolant.