I'll go ahead and share my movie idea from yesterday.
It's like Who Framed Roger Rabbit, but with anime characters instead of cartoon characters. The plot would be about a rejected anime character who befriends a boy, and together, they try to get the character his own anime.
The movie would be set in the year 2000, so only anime from before then can be in it. The protagonists would meet characters like Sailor Moon, Doraemon, Astro Boy, Speed Racer, Totoro, Lum Invader, Detective Conan, Anpanman, and Sazae-san. There'd also be battle shounen protagonists like Goku, Yusuke, Kenshiro, Kenshin, Seiya, and Luffy (his anime started in 1999). And of course, there'd be cameos from obscure anime.