I was at the airfield on infiltration when I came upon some warhead looking things all stacked up, so I figured "Hey, these never explode on other games!" and my friend said "Shoot them!" So, I did, and it did nothing, I began to laugh shooting the warheads, when BAM! As my friend explained what he saw as "You was just engulfed by flames" My body was never found, and the giant smoke plume was visible from where the infiltrators were.
Another, was we were driving to a secondary objective on Dragon Rising, and I was the driver, my friend the gunner. He was just a little chatter box, then shot downwards, after which the first thing he said was "Wow, I can almost hit the jeep." As it slowly went to a stop, he noticed I had slumped over the wheel, with a huge gash in the back of my head, yup, he just freaken shot me.