Airline Fare Codes – Airline fare codes are a way for airlines to differentiate between class of service, cost of ticket, award ticket, etc. and they differ greatly among each airline. This site can help you understand those fare codes for current and/or future travel.
Flight View – Online Real Time Flight Tracking
TravelDudes – For Travelers, By Travelers!
Travel. State.Gov – World wide travel information (i.e. travel alerts) for US passport holders.