I cannot say enough good things about the concierge staff.
In LAX there is David who is extremely helpful. There are the numerous ladies at YYZ who have helped me many many many times.
Some of the items they have helped me in the past are: they met my late evening flight, when I was travelling from Central America, with flowers that I had requested for my wife's birthday, taken care of flights where there have been cancellations, in ORD take took care of a FedEx letter that needed to go out after working on some docs on the flight, they have helped me in YEG, YVR and of course the ladies at FRA.
Concierge take the time to listen and help you out at a time when very few of AC front-line staff are willing to.
Cheers