I think the kind of unexpected I really love is when you open books and the actual way of writing is different and interesting. Like reading Virginia Woolf for the first time or Lawrence Durrell for the first time.
I'm writing a novel about two actresses who go to New York, because that's what I know about. One has lost touch with reality, disappears and is picked up by a man.
The difficulty of writing a good theatre play set in new reality was even greater given that the level of similitude to life that is allowed in a film would not work on the stage.
When I began writing science fiction in the middle '60s, it seemed very easy to find ideas that took decades to percolate into the cultural consciousness; now the lead time seems more like eighteen months.
As for the historical inspirations I drew on in writing The Snow Queen, I suppose I would call them more cross-cultural inspirations, though they frequently involve past societies as well as present day ones.