When I was a kid I bought a big set of
glow-in-the-dark adhesive stars and decorated the ceiling of my room with them. The ceiling was sloped on the sides because it was right under the
apex of the roof. It really was like having my own personal
planetarium, although I didn't bother to arrange the stars as they actually appear in the
night sky.
I spent many nights reading great books, then turning off the lights and thinking over the stories under those phosphorescent stars... What bliss!