Remember when you needed a case for your travel documents? Find another use for it, because one of the last scraps of important travel-related paper, the boarding pass, is headed for the recycling bin. As the industry has embraced 2-D bar codes vs. the relatively expensive magnetic strips on old-fashioned boarding passes, the location of that bar code — on a pass you printed at home or at a kiosk or on a Web-enabled cell phone — has ceased to matter. So has where you checked in; you can do that from your phone.
Continental leads in the adoption of smart-phone boarding-pass technology, allowing passengers to board with electronic passes at 42 U.S. airports, followed by American (27 U.S. airports), United (18, which will add to Continental's total, now that the two carriers have merged) and Delta (17).