To offset the impact of rising fuel prices, the airline industry is doing the obvious: retiring less-efficient aircraft, flying slightly slower, and plugging into electrical systems when parked at the gate. But even smaller steps, multiplied over a large fleet, can have a significant impact. Various airlines are carrying less water for the facilities and seeking out passenger seats and drink carts made of lighter materials. Delta is considering asking its cockpit officers to share pilot manuals so that one set of books can be left at home; Northwest considered serving soda out of plastic bottles instead of cans (though ultimately decided that customers would revolt). Employees are also washing planes more often to keep ’em from being weighed down by dirt. And if you think a little grime doesn’t make a difference, Southwest Airlines estimates that it’s saved $1.6 million on fuel since April by doing an extra power wash each night.