It might (and probably has been) suggested before but since I couldn't find it (not an expert forum user :)) I'll give it a shot.
Since we have many gestures now, including sitting down, why can't we have a "fake death" animation?
The idea came to me when I was prone near another dead body looting it, when another player run over to me from behind a building. I literally thought I was done for, since I didn't have a weapon in my hands. Funny thing is, the guy just run to the other body, and started looting it. It occurred to me that very moment that my would-be killer thought I was already dead! :D.
I pulled out my 1911 and placed a bullet in his head.
Now I know I was extremely lucky but it got me thinking. How many times have we witnessed "playing dead" as a survival tactic in movies or RL? Hell, it's a natural procedure designed by evolution itself. Hard to see it not being an option in a game focused on SURVIVAL.
Now imagine using that tactic when you start hearing sniper shots fired at you an you're in an open field. You just drop down hoping the sniper will buy it.
I know that once the option would be implemented most snipers would just "double tap", but still 1/10 might just let you off.
There should be some restrictions of course, as the feature should practically be an all-in gamble. E.g. Trying to move or look around should break the animation.
Also, I have no idea how would that perform once ragdolls make it into the game, but on a side note, I wonder how "unconscious" will work with ragdolls as well. Death with ragdoll and falling unconscious with an animation will clearly be distinctive -> double tap.