Where as I agree with all those who say anything can be a dangerous weapon, (I even had my spoon taken off me from security!?) if someone came at me with an icetong, glass bottle, credit card etc, I would have a good go at fighting back, and I am sure people would come to my aid, however a knife is different. A hijacker can kill quickely and easily with a knife, but if his weapon was say an icetong, it would take longer, and he could then be overpowered by other people. If the hijackers on that dreadful day had icetongs, glass bottles etc as weapons, I think the outcome would have been different.
I am quite concerned about the crash axes on board though!