I finished playing through for the first time, and didn't catch anything particularly striking like in F3, where you can nuke Megaton. I still go back to F3 just to see that over and over again; the first time it literally made my jaw drop. I was just wondering if there is something similar that I haven't seen in FNV. I don't want a spoiler or anything, tho.

There is a moment which involves REPCON that's pretty awesome.

Falling through the floor in the game and when it crashes/freezes up. Those were my OMG moments...

That first Cazador.

ikr and when a lakelurk swimmin under a platform I was on just popped up in front of me screamin in my face lol...

Yep.
This one sticks out in my mind. I'm on my second (full) playthrough and, so far, other than Boone's quests, that's about it.
Well, I consider the travel up Black Mountain (listening to the radio signal along the way) as an on-going OMG/LMAO moment.

:lol: Not quite what I meant, but still I lulzed.

Nice, I'll have to look out for that next time, didn't catch it in the first playthrough.

Another moments are when I finished the quest that involves the Blue Star Sunset Sarsaparilla. Meeting the legendary deathclaw for the first time. Getting the Advanced Mk II Power Armour .

Vault 11

There is a very similar topic, let's use that please.

http://www.gamesas.com/index.php?/topic/1123130-your-1st-epic-moment/