Speaking of Mexican Standoffs, the absolute best example of one is one of my favourite scenes from any movie ever: the three-way standoff in
The Good, the Bad and the Ugly.
It's basically five minutes of people looking shiftily at each other, but the music combined with the camerawork gives it this
amazing feeling of tension.
Unfortunately, I can't seem to find it on Youtube, but
here's the music I was talking about.