Curbside Check-In: $2-$3+

Most airlines, including the nation's largest, American Airlines, charge $2 (plus tip) to check your luggage at the curb. Delta stands out, though, having recently raised its charge for this service to $3 (gratuity not included). Even some skycaps are upset about the fee hikes, since the charges have cut into some of the tips travelers leave for the workers. In fact, a federal jury in April ordered American Airlines to pay more than $325,000 for damages incurred since the fee began in 2005 to nine skycaps at Boston's Logan International Airport; a few weeks later, American dropped the $2 fee.