The American Astronomical Society offers its monthly list of job openings in astronomy (the ``Job Register'') by anonymous FTP from the directory blackhole.aas.org:jobs/jobreg. Note that usually only the latest month is kept as an on-line file. Contact ssavoy@blackhole.aas.org if you want to be on the mailing list.
STARJOBS is an electronic notice board maintained at the Rutherford Appleton Laboratory and sponsored by the European Astronomical Society (EAS). Telnet to star.rl.ac.uk or SET HOST RLSTAR and login as starjobs. You will enter a hierarchical help library at the subtopic called JOBS. To read a job notice type the first few characters of the title of the notice and follow with a carriage return. Note that there is no facility for mailing back the notices to you. For local hardcopies it is best to keep a log of your session or cut and paste to extract text. See the EAS Newsletter No. 7 (Jan. 1994) for more details.
Under the URL http://chronicle.merit.edu/ users can find an electronic listing of academic job openings in all fields, including astronomy. This service is provided by the Chronical of Higher Education and contains primarily but not exclusively openings in the United States.