Our street organised an advent calendar where different houses would display a decorated number in their window on each day of December leading up to Christmas.
We got allocated the 24th and so took a photo of each window done before us and created an animated 3D scene. We back projected this onto a sheet hung in front of our window.
This is a video of how it looked from outside taken with a video camera.
This is a video of what we projected (better quality than the camera version)