On a Google group, called "הזדמנויות."
Since May of 2009, Martin Kaminer has been posting job opportunities on Hizdamnuyot (Hebrew for "opportunities") on an almost daily basis. Many, but by no means all, are in Jewish organizations and/or non-profits in the United States; listings range from senior management to administrative assistants and teachers. It costs nothing to join the group and, even more incredibly, if you are an employer, and Martin thinks your job opening will be of interest to his subscribers, he'll post your listing free of charge.
No one is really sure how Martin finds the time to do this, but then again, no one is really sure about lots of things about this "unsung hero of Jewish start-ups."
Join the group by registering at hizdamnuyot.com. Publicize a job opportunity by sending Martin an email at firstname.lastname@example.org. It is that easy.