Going Postal (Discworld)/YMMV

The book

 * Genius Bonus: The 'Agatean Wall' Vetinari and Slant reference when the bankers are meeting the Patrician is not only a real thing but is basically exactly what Slant described. In real life, when somebody on Wall Street is given knowledge of an upcoming deal - for instance, a merger between two companies - that will affect a stock's price, they are said to have gone 'over the Great Wall' and are henceforth forbidden from commenting or acting on that information. Of course, in our world, insider trading and such is generally...not looked highly upon, but at the heart of it they do just agree not to do it.
 * There is also the term "Chinese Wall", with a slightly different meaning that comes closer to the one used in the novel. These ethical "walls" are erected between departments in a business in order to reduce the opportunity for the business as a whole acting on insider information. And, while the term is culturally insensitive and inaccurate (and has been called that since before PTerry wrote the novel), The Agatean Empire is the Discworld's version of China.
 * Harsher in Hindsight: Mr. Pump's "When banks fail, it is seldom bankers who starve" has a much harsher ring to it post-2008. Needless to say, the live-action adaptation made in 2010 (see below) emphasised this more strongly.
 * Also, Moist mentioning that The Trunk is "too big to fail"
 * Reacher Gilt's plan is, word-for-word, exactly the type of scheme that Mitt Romney was accused of doing repeatedly as part of Bain Capital during the 2012 US presidential election. This may be Hilarious in Hindsight to some.
 * Magnificent Bastard: Moist is a brilliant rogue; Reacher Gilt is to corporate crime what Moist is to street crime and someone who Moist himself admits could mentor him in Magnificent Bastardry—a man who has figured out how to do basic conman tricks like rigged three-card monte...with entire banks. In the end, they're both way out of their league when they go up against Havelock Vetinari.

The TV adaptation

 * Fetish Fuel: Adora, clad all in black, cracking the riding crop and telling Boris (the horse) he's been a very naughty boy puts one in mind of other types of women.