Lost sun glasses.
I know of one posing a...hole, who, upon being invited to a trip on a rather large yacht, went out and got himself the most expensive Ray Bans he could find.
Questioned why there was a bit of string in the box, and on being informed it was to be attached to the shades and looped round the neck to prevent loss.
Only an idiot would need to do that, according to our man.
Moments later he confirmed what everbody thought and his expensive shades disappeared in to the Menai Straits!!!