So many times when I return to my PC I am greeted with aggressive players because I haven't replied to their message...
When you leave your PC (to take a leak or to make a drink etc...) you should be able to let other players see this via a player status icon in the list next to your name.
Please add the ability to set an 'AWAY' status to alert other players of your temporary absence.
Even if it is just a red dot for away & and a green dot for playing.
Also when you change your status a message in the chat saying 'AWAY' (in red) & 'PLAYING' (in green)
((Player Name)) Status AWAY
Then when they return the chat notifies that you're playing again...
((Player Name)) Status PLAYING
This means on large missions you could hide your character, set your status to 'AWAY' and just minimise the game and leave it running and return later.
This feature could also be used if you simply want to play the game without talking to anyone and not appear ignorant by not replying, for example people asking to group up with you on missions like wasteland, etc... :-)