Orbitz, Expedia, and Travelocity. Priceline. Mobissimo.com searches airfares across online quote providers, including airline ticket consolidators. Consolidator links. Tips on using frequent flier programs at frequentflier.com and howstuffworks.com. Ticket upgrade tips at upgradebuddy.com. Much advice at Edward Hasbrouck’s The Practical Nomad. A guide to sleeping in airports. A Monkeyfilter discussion about cheap plane tickets.