General Disclaimer of Everything: I acknowledge and accept that I own neither Harry Potter or Discworld and that I am only a child playing on the beach while vast oceans of cannon lie undiscovered before me.
Lord Havelock Vetinari, Patrician of the Confoederatio Helvetica (Better known as Switzerland) showed very little reaction when the prisoner was brought before him. He simply continued to drink his tea as the man was deposited, trembling, on the floor and the guards shut the door behind them. There were several minutes of silence that were only broken by the occasional whimper. It was only after he finished that he turned to address the man.
"I dislike mimes." He said lightly. "They are the lowest common denominator in any room. They are an affront to the sensibilities; tragic parodies of humanity that exist to be laughed at. They are insubstantial, and produce nothing."
"Do you know what else I dislike, Tom Riddle?"
Vetinari paused for an answer that he knew wouldn't be coming. Voldemort could only quiver in response.
"I dislike terrorists. They too are tragic parodies that ultimately accomplish nothing. A waste of time, space, and air. Even worse, they disrupt the balance. My citizens become unhappy when they lose their stability, and when my citizens are unhappy, I am unhappy. Do you understand?"
One elegant eyebrow ticked upward.
"While you were only toying with the politicians, I was willing to let the British Government deal with you. After all, sometimes you must let the children fight their own battles." Vetinari's tone was calm, but something hard and cruel was lurking in his eyes. "But terrorizing a school… preventing the sacred art of learning… halting productivity… You went too far."
Then Vetinari pulled out his final, most dangerous weapon… Irony.
"You desire to live forever, Tom Riddle. Instead you will spend the rest of your short and miserable life begging for death."
AN: And so ends Tom Riddle. A bit anticlimactic, I'm afraid, but hopefully still true to Terry Pratchett(May he rest in peace) and his love-able characters.