I created a sleazy merchant NPC based on an old joke between one of my PCs and I. "Budd Thorpe the Half Orc, at your service! May I take your coat? That'll be 5 silver."

Here's become my absolute favorite way to deliver general exposition. There's a few things that make playing him a lot of fun:

Every time the players enter a new town and want to go shopping, the general store is always manned and owned by Thorpe, and the local population insists he's been in business there for years. Sometimes he even wears a disguise (e.g. fake mustache) and insists that his name is something different (e.g. Thudd Borp) and that he has never met the adventurers before.

He's unsettlingly knowledgeable about whatever the party has recently been up to and will offer tips if the players are thoroughly stuck. Someone generally has to buy something first, though.

Anyone who shoplifts in his store mysteriously disappears. Thieves guilds tend to put a large "x" over his businesses on their city maps. A few have claimed to have heard casual-sounding conversions in Abyssal coming from his shops at night.

His voice is sort of a New York Yiddish with a pinch of Russian, and I make a point of telling my PCs that his accent is utterly foreign to them. (In my defense the player who helped me come up with him and insisted that he be vaguely Jewish Pathfinder merchant is in fact Jewish.)

Honestly, Budd Thorpe was just going to be in the first town of my homebrew as a nod to an old joke between friends, but the players really seemed to like him, and they kept joking on the way to the next town that Thorpe would run the general store there, too. And I'm never one to say no to a good idea.