[ajb]

Maybe an 'anyone opting out on my flight' app would be a good idea. Although writing one would probably get you put on the terrorist watch list.

[jpalomaki]

Offline version could be to wear a certain pin to indicate one is a member of the "opt-out movement"

http://www.pinmart.com/stock-pins-awareness.aspx

[krichman]

That would be nice; you could actually have people on multiple flights opt out because there's a single security checkpoint for multiple gates.