(you can bypass the slow check-in lines at lobby-check-in)

- when returning a rental car consider going to the curbside check-in first to check your bags
- be sure your flight has not been cancelled
- be sure your flight has not been substantially delayed (you might catch an alternative earlier flight)
- be sure the checker uses the correct destination tag with the correct flight number (or numbers)

This tips are even more important if you use a hotel-side check-in: SAS-Hotels, Swissotels for SR, Kempinski for LH, etc.

(from the airline passengers guerilla handbook).