The funny thing is . . . . . . it generally turns up somewhere else. Often not very far away from where it went missing.
I have been looking for it ever since I got home and its just gone I did think that LDRed may have some clue as to where to look , seeing he is always losing things, but even he is not telling me.
I've never seen him disappear as such But he has had the good grace to at least look a bit shifty for a few minutes until someone else buys one and normal order is restored.