* Internet and wireless check-in. You can check in for your flight through the Internet on Alaska (since 1999), Northwest (since 2000) and, new this year, Delta (frequent fliers only). The service was briefly suspended in some cases after Sept. 11.
Northwest also has begun letting some of its customers rebook flights on the Web or on wireless devices such as PDAs. You can also check in and pay the change fee, if any, on the Internet or at the self-service kiosk at the airport, bypassing the ticket counter.
* Self-service kiosks. Most of the majors also provide computer kiosks at airports where you can check in for your flight. Alaska and Continental are ahead of the pack in installing the units. As of early December, Alaska was operating these in 72 of the 75 U.S. airports it uses, and Continental at 87 of 122.
Kiosk customers with baggage to check generally must still go to the ticket counters or use curbside check-in. But in Portland, Ore., you can use Alaska Airlines' kiosks to print out your baggage tags and attach them yourself. (All bags are scanned, an Alaska spokesman says.) United has phones in its kiosks that let you contact reservation agents.
* Online award travel. Frequent fliers achieved a small but welcome victory this year when Alaska, American, America West and Delta began letting them book award travel online; Northwest and United already allowed it. Previously, customers could redeem the miles online but then had to call or send an e-mail to book the trip.
Jane Engle welcomes comments and suggestions but cannot respond individually to letters and calls. Write Travel Insider, Los Angeles Times, 202 W. 1st St., Los Angeles, CA 90012, or e-mail email@example.com.