I've always felt a little left out because I never learned it. (At least, not until I looked it up in college, and by then, I was too old to use it.)
When I was a kid, it always felt a little strange to hear about it because "pig" and "hebrew school" don't really go together.
In any case, yeah, I've always seen it spelled the way Anna has it.
I think it was used a time or two on the show (maybe by the Prankster or his assistant?), but I might just be thinking of a scene from The Mask.
Oh, and of course, everyone knows "ixnay," right? It's practically become a "real" word.
Paul