On my way to this evening’s mob I saw a sign in a dry-cleaner’s window.

Your clothes can be tested for SHATNES
By the SHATNES LABORATORY

Huh? SHATNES? I figured it was either (a) some kind of Jewish thing—in these parts, frequently a good bet in moments-of-unfamiliar-vocabulary—or (b) it was a toxic chemical, like PERC. Those all-caps seemed suspicious to me. Or maybe it was (c) some kind of Star Trek reference: Do your clothes make you look like a polyester starship captain with a bad rug and diction issues? Our laboratory can find out.
Anyway, this is why I love the internet: it took me mere moments to find out that the answer was (a). Kosher clothing! I knew about the ‘no mixed-fiber fabrics’ rule, because it comes up in the same abominations-unto-god list as ‘no queers.’ (Thank you, Leviticus.) If you, like me, have wondered if there was anybody who gave both rules the equal gravity that god apparently intended…wonder no longer.