I think the ones that tugged most at the heart strings are the calls where they really do know that there is no way out rather than those who maybe made the calls but still had some hope.

The guy who called his wife from a meeting room and when she said get out, he told her people are jumping out of windows from above. That feeling of knowing you are going to die and there is no way out.

Horrific, makes you realise life can take a turn at any time.