Gingaza (Galaxy) Planetarium

If it wasn't for the faux-Nasa space shuttle on the outer wall, you'd probably have a real hard time finding this planetarium, hidden away far out in the wilds of Katsushika-ku. You see, the Gingaza isn't just far from nearby stations: it's housed inside a Buddhist temple, making it the first of its kind in Japan (and most likely the world). Essentially a one-man show run by starstruck monk Kasuga, the planetarium features a different programme every month, with the show narrated live by Kasuga himself and a female assistant who combine for plenty of informative tidbits and comedic value. The problem is getting a seat – reservations are taken only on specified booking days and then vetted by lottery. Check the official website for details (in Japanese only, natch).