"Queer as folk" strikes me as a particularly British expression (what the heck does it mean, anyway? 
).
There's a proverb, "There's owt so queer as folk," meaning "There's nothing as strange as people." You say it when someone's done something inexplicable, usually in a Yorkshire accent: "There's owt so kware as fawk*". In the UK the show's title is also a play on "queer as fuck" as in "homosexual as anything".
*I can't quite put the vowel into print, it's somewhere between the aw of walk, the o of folk and the oh of fog (but not your American fahg).
