A friend recently travelled with his wife to Minneapolis (airline to go unnamed). As per his usual practice he stored his backpack under the seat in front of him and then proceded to plug himself into his talking books. Apparently, he inadvertantly pushed the pack far forward. When a passenger claimed that seat and found the pack on the floor, he gave the pack to the stewardess saying, "Someone left this here." She proceeded to remove the pack from the plane without checking with any of the surrounding passengers. When my friend decided to put his iPod away, he discovered his pack missing from under the seat. Upon asking the passenger in front of him whether the pack was at his feet, he learned the fate of the pack. Now for the caution, it took over two weeks, making some 30+ phone calls and experiencing much rudeness and lack of cooperation from airline employees regarding his pack. Apparently, carry on does not rate the same "protections"(hah!) as checked bags and the airlines owe you nothing. What stuck in my friend's craw was that he had repeated phone calls with an employee who had the pack sitting in her office and who refused to help him. Eventually she ageed send it to him when he prepaid FedEx to do so. He eventually did that and his pack was returned to him (with nothing missing!). After a written complaint to the company, he was quickly reimbursed for the FedEx costs. The moral of the story? Keep your eye on your underseat luggage. Luckily he had nothing of value in the pack: a few books, writing implements, a paper notebook, a sweater and jacket. Had it contained his laptop and/or other expensive gear, who knows how "lucky" he would have been.