I know you can change the suppression gas levels in game zones on the fly.
Mabey you could change all the gas in every zone to 100% for about 10 minuets on sept 11 as a moment of scilence? In respect for the people who died due to the terror attacks, and the people who have died since fighting terrorism?
Just a suggestion.( Yes I would put off quitting for 6 more days if this would happen:P )