I wonder if Robert Jordan was inspired by this when he wrote The Great Hunt (spoiler follows, I guess!) The protagonist experiences a hallucinatory battle with his arch nemesis, then learns that it was somehow projected in the sky:

"In the sky?" Rand said in wonder.

"Both of you," Moiraine said. "Your battle took place across the sky, in full view of every soul in Falme. Perhaps in other towns on Toman Head, too, if half what I hear is to be believed."

This then ruins his plans of keeping a low profile. Those books had some fun ideas.