computer hardware; computer programs for use in the fields of wired and wireless communications; power supplies; modems; communications switches; radio controllers; radio transmitters; radio receivers; radio transceivers; radio power amplifiers and exciters; radio base stations; satellite controllers; satellite transceivers; satellite transmitters; satellite receivers; paging controllers; pagers; two-way pagers; paging encoders and decoders; personal digital assistants; integrated circuits in the field of wireless communications; circuit boards and modules for use in wireless communications; paging terminals; voice messaging terminals; electronic mail terminals; fax terminals; toll calling terminals for implementing pre-paid wired and wireless communications