Photoactive compositions of matter, methods for their design and synthesis, and various applications of such compositions of matter are disclosed. The method comprises receiving, from a non-subscriber to a service, a request for real time communications with a subscriber to the service and providing real time communications between the subscriber and the non-subscriber. The unit can include a packing injection system, clamp, and novel packing configuration. The background portion can be continually broadcasted by the head-end. The seal line includes a liquid crystal inlet. The motor includes a motor body and a housing, both of which have the same features as those described above.