It's 2 am, and I'm having one of those frantic manic thinking fits. I should have a gin or something.
Anyway, thought the third...
Was just thinking about the metadata issues I posted about a few days ago. And the image of searching through a photolibrary brought Shooting The Past to mind.
If you haven't seen it, do so immediately. If you're working with metadata or archives of any sort, it's a salutatory lesson in 'remembering the value of human quirks'.