It's not only good characters, either, for I often find coercive, mean characters, whose behavior I found reprehensible in a story, pop into my mind. Other times a character from an otherwise unremarkable story is so strong they break ground and plant themselves in my imagination.
What is this? Some sort of psychological archetype trick of the mind? If that is the case, I'm sure everyone has different characters hopping around in their cerebral cortex, but isn't it rather interesting who shows up?
The trick, of course, for writers is to make sure those characters don't show up in one of their own books. Which is another interesting phenomenon, because often my book characters show up in my brain long before they do a book.
How about other authors? Do you have similar occurrences?
Short Stories from the Aegis World
Available from Wing's Press