Possibly the best moment in Discworld is at the end of Guards! Guards! - showing Vimes and Sybil's blossoming relationship in the perfect terms — (paraphrased):
'What was it? Oh, yes... it's a one-in-a-million chance, he said, but it just might work.' And she smiled at him. It occurred to him that in her own special category of women, she was quite beautiful - and that was the category of all the women, in all his life, who had ever thought him worth smiling at. [...] The woman was a city.
Vimes witnesses what he briefly believes to be the deaths of Colon, Nobby, and Carrot:
The crowd watched in bemusement as the superhot blast flung it into the sky and barely noticed Vimes as he pushed his way, wheezing and crying, through the press of bodies. [...] “Thirty dollars a month!” he muttered. “That's what they died for! Thirty dollars! And I docked some from Nobby. I had to, didn't I? I mean, that man could make a melon go rusty!”
Vimes is still mentally reeling from Vetinari's analysis of the human condition when he, Carrot, Colon, and Nobby come in to recieve their reward. They ask for nothing more than a five-dollar raise, a new tea kettle to replace one they lost, and a dartboard, restoring his faith in humanity and leaving Vetinari himself stunned.