This morning, I was taking a flight to Detroit on Northwest and using their automated kiosk to check in.  During checking in, the seat selection screen was filled with options and additional prices that you could pay in order to "upgrade" your seat from a middle seat to a window or exit row.  Ok, I guess I can live with this minicharging mentality – they probably really need the extra 15 bucks anyway.  After that screen, however, the next one was a marketing screen encouraging me to sign up for the Northwest Frequent Flyer program.  Going through that process, it strikes me that checking in for a flight is the last situation where you would want to be interrupted by marketing.  Except maybe checking into an emergency room.  Sometimes the smartest marketing you can do is to help your customer get through a necessary interaction with you in the fastest possible way.  Just imagine if Northwest, or any other airline, could master a "one click" check-in process based on stored profile details like Amazon or any number of online retailers.  I’d tell everyone I know to sign up for a frequent flyer program that could do that.