Spam for Jews

Every day my e-mail inbox is saturated with tons of spam containing benign stock alert attachments like the one on the left. Usually I can identify them before even opening them, and they end up going to the trash en masse.

But today they got me. I fell for it. What made me open this particular spam stock trading tip, sent by "Richard Fulton"? It was the header:

Subject: Yarmulke

Boy, these spammers are clever!