When I sit down to write (like 'write' now) I often have no idea what I'm going to say. I try to surprise myself. A friend of mine asked for a story idea. Here's what I said.
man awakes to find his wife and children have been replaced with others
who know him, but he doesn't know them. When he looks in the mirror,
he doesn't recognize himself. He pushes
through this and gets in his unrecognizable car which he is oddly
certain is his. He starts out to work and drives aimlessly to a place,
parks and goes in. Everyone knows him. He walks to an office, sits
down and logs into the computer with a guessed password. He starts
reading email and making up replies. A meeting notice comes up, and he
goes to the meeting full of strangers that know him. At the end of the
day he retraces his path to "home", has dinner with his "family", makes
love to his "wife", and goes to sleep. In the morning, he wakes up and
is greeted by a whole new family, wife, house, car, job, and guessed
I thought it was kinda fun.