My own unplaceable:
‘Your mother was a lizard and your father was an atom (?) bomb.’, which I assumed to have been hurled at Godzilla, but can’t find a source. (ie ‘How do you insult Godzilla?’)
Others you struggle with, or ‘swear’ must be from MST3K or riffed/reffed therein, but just can’t…?
Probably a takeoff on the Frenchmen’s insults from Monty Python and the Holy Grail. (“Your mother was a hamster and your father smelt of elderberries…”)
I searched and searched to no avail. It seems we should have a thread for this topic, and if we do, please movie this for me. But if we don’t, let’s start one. (I know we had one with pictures, but that seemed like more of a guessing game thing, and I might have blocked it)
I did look at annotated MST for this but came up empty, so maybe this isn’t MST, but CT? But I know it was Joel, singing, “Little Audrey Said…”
I was watching some animated shorts (Terrytoons Farmer Al Falfa, Little Lulu, etc) and came upon a few of the Little Audreys, and I was like, so that’s where Joel got it.
Here’s the song
It’s definitely MST3K. I can hear Joel singing it, too. I want to say it’s from one of the Hercules movies, but I’m not positive.
It’s over here! We’ll shift this over there presently. 
Thanks - yeah that’s a bit of a mouthful for a title. I’ll try to think of some tags we can add, might help others with a search.