#RPGaDay 2016 Day 28: Thing I'd Be Surprised That a Friend Hadn't Seen or Read
Actually I've had this happen to me recently... Given my group has some folks younger than me, I've gamed with people who have never seen Star Trek in any incarnation.
That's not too shocking once I gave it some thought. Star Trek: Enterprise debuted in fall of 2001, some fifteen years ago. And it was not a particularly popular Star Trek. Someone who is thirty now would have been around fifteen then. And Voyager debuted in January of 1995, so you're talking being under the age of ten for that!
There's certainly a things I've not read or seen that are on other people's "I can't believe you've not read/seen that" so I've no judgment. With that caveat, there's a few other things I'd be surprised a gaming friend hadn't seen - Butcher's Dresden Files, the classic Star Wars trilogy (I know a number of people who swore off the prequels), Lord of the Rings (whether in film or novel form), and A Song of Ice and Fire (novels) / Game of Thrones (television). And Lovecraft. Gotta read some Lovecraft...