It's auto-matic

Because business travelers hate waiting in line even more than vacationers do, major rental-car companies have programs to speed up check-in for people who are pre-enrolled. In some cases members can go straight from the airport terminal into the driver's seat of their car.

Hertz's No. 1 Gold Club (800/654-3131) costs $50 a year. Members fill out a master contract, and Hertz keeps their personal data, preferences, and credit-card numbers in the computer, eliminating the need to complete forms with an agent at check-in. At 38 major U.S. airports, members go directly by shuttle to the Hertz Gold Canopy, where their name is posted on an electric sign above their waiting car, which has keys and a preprinted rental agreement inside. At more than 200 other U.S. airports, members have a separate check-in counter where they can pick up a pre-printed rental agreement and keys. There's also a Hertz No. 1 Club, which has no fee; members must stop at the check-in counter to show their license and credit card, and to sign a rental agreement.

Avis (800/331-1212) has a similar two-tiered program. To join the no-fee Avis Express, you apply for an Avis Wizard number and provide some personal data to be stored in the computer. Members must stop at the counter to show a license and credit card and sign the rental agreement, but the process is faster than for nonmembers. Avis Preferred, at $50 a year, lets members go directly to their waiting car at airports where a shuttle ride is required; otherwise, Avis Preferred members' cars are waiting outside the terminal door.

Budget has a no-fee Budget Express program (800/255-5520) in which a preassigned ID number lets members show up and sign a preprinted rental agreement at check-in. Budget also has a separate reward program for frequent renters called AwardsPlus; members earn free rentals based on the number of paid Budget rentals they accumulate.

National's Emerald Club (800/227-7368) costs $50 a year. At 77 U.S. airports, members check themselves in at Smart Key machines, where they can select a car model on an interactive screen and obtain keys. At 49 airports, members can choose any car on the Emerald Aisle, including luxury models, at no extra charge if they have booked a midsize car.

Alamo recently waived the $50 fee for joining its Quicksilver program (800/882-5266). Like National's program, it offers self-service kiosks at 52 major airport locations. Alamo also has a rewards plan for frequent renters, called True Blue.