Mine happened tonight in primm next to the bison steve casino i was on the rollercoaster track me and my companion boon just killed an escaped convict (i looted him) and i went further up the track to it's highest point and i went down the otherside when i saw the track was busted so i looked around and saw another track below me so i made a total noob move and jumped down to the other track (and died).

Siding with the NCR. I role play later on in my character's story that he leads a somewhat "rebellion" against them after their annex of New Vegas and that he turns into the one that runs New Vegas now. Should have sided with Mr. House or gone independent. That reminds me of my other mistake, killing Mr. House.

Siding with the NCR in my first playthrough.