Sometimes a passenger will complain because they just don't understand how things work. One night the lead F/A relayed this message from a pax: "Tell the Captain he needs to raise the cabin pressure." I sent a message back that we had double-checked and everything was working just fine. Well, when we were deplaning, here came a scowling little old lady, who snapped: "TWA always fixes the cabin pressure for me!" I mentally saluted my TWA colleague, who had obviously come up with a better response than I had, something like: "Thank you Ma'am -- we'll adjust it right away!"