Yes, I actually lost the small cross bodybag with my passport in it at an airport last week! For the entire holiday the bag had been practically surgically attached to me, and then for some unknown reason I took it off when I sat down for coffee and then walked off without it.
Thankfully, I realised quite quickly, went back and it was still there, but it gave me quite a moment.
I'm usually very sensible about these things, hence the bag style.