Southwest Airlines does a sort of hybrid first-come, first-served seating that creates a fascinating game theoretical problem at the airport.

As you check in you get a boarding pass in group "A," "B" or "C," and the groups line up and board in that order. No assigned seating. The result at the gate is a somewhat complex waiting game. If everyone cooperates, we all get to sit until right before it's time to board. But inevitably a few people start lining up early, which starts a stampede. And then everyone ends up standing in line for a very long time. Here at gate A7 at the Albuquerque airport, where I'm sitting waiting for a flight to Phoenix, people have been lined up for half an hour for their flight.

The benefit of this group behavior seems minimal, but I admit I've done it myself more than once. Today, I'm sitting.