"Sir!" you shout at the offender. "Thou art a boil, a plague sore."
"Uh...what?" the man asks.
"Would thou wert clean enough to spit upon," you answer.
He raises a quizzical eyebrow and says, "Is this about the quarter?"
You say, "Away, you starvelling, you elf-skin, you dried neat's-tongue, bull's-pizzle, you stock-fish!"
"Oh...okay." The man steps away, retreating from your ferocious onslaught. Having won your battle of wits, you flex for the crowd (it's a metaphorical crowd, of course, as not even the cashier gives a damn about what's going on) and leave to head home. You awake with another dream successfully complete.