I've found a fair few, but not all of them I can truthfully say that I understand. On the upshot, maybe when i see a film, something weird will remind of of New Vegas, and i will then understand the encounter?
I have understood most of them, and out of those, i have enjoyed most of those, so i would say it is worth it.
Let's see..the ones I have found so far that I remember (Should be obvious since this is the spoiler section, but just to be painfully clear...)
*SPOILERS*:
1) A fridge with a skeleton wearing a Fedora. (Think of the most recent Indiana Jones film, where the trope "Nuke the Fridge" comes from...)
2) Leaving the factory where one finds the..ahem..sixbot, 4 old ladies tried to mug me, each of them weilding rolling pins. (I think a Monty Python reference, they did do a sketch called "Hell's Granny's" if I recall right)
3) To the far north there's a UFO hovering near 3 aliens, the aliens are hostile. One of them does have an alien blaster and some ammo. If memory serves the aliens replace a "normal" encounter of 3 mercs, one with a unique gauss rifle.
4) The Latin Graffiti mentioned in another post (Another Monty Python reference, From "Life of Brian")
5) The conversation with Rex where he mentions Jimmy fell down a well, again mentioned in another post. (Reference to the old Lassie TV show I assume, where Lassie would come to town trying to bark and explain that Timmy fell down the well or some other disaster).
6) Found in Nipton, two chared corpses named Owen & Beru (From Star Wars. Luke Skywalker's uncle and aunt)
I may have seen one or two more, those stuck out in my head though.