Left an iPod on a plane in CLT about two years ago. Realized my mistake on the rental car shuttle and went right back to the airport. It wasn't found.

Left my Shure headphones on a plane at SFO a few months ago. Realized my mistake a few days later. They never turned up.

Left my crappy old cell phone on a plane at LHR about two years ago. Realized my mistake about a day later. It never turned up

Left my shiny new cell phone on a plane at LAX about six months ago. Realized my mistake about 10 minutes after deplaning. Ran back to the gate, the GA was less than helpful, but I eventually got it back ^

Left the most valuable item of all, a journal, on a plane at DFW about three years ago. Realized my mistake a day later. I got it back ^ ^