I had a transit a Beijing Capital (PEK). I made the fatal mistake of leaving my ebook reader on the plane. At this point, getting it back seems impossible (short of going back for it in person). I tried quite a lot.

I lost my item on the way there and on the way back I already asked the airport information desk if there’s a lost-and-found and whether they found any item like mine on my flight’s day. Amusingly the information person at an international (transit) airport spoke absolutely zero English. After a short machine-translated exchange I was given a negative answer. But I didn’t give up.