If you're in the Nakano area west of Shinjuku, possibly to stay at Tokyo Hostel Fuji, then there's a nice little neighbourhood temple that's worth a quick visit.
The most interesting point for me was the small statue of, well, I don't know. It appears to be a snake with a human head, something I've not seen at any other temple. Is it a Buddhist deity? If so, I'd have thought I'd have seen it before, as I do visit a lot of temples.
As well as this, there's a handsome, broad worship hall, a couple of other Buddhist statues, an unusual but pleasing abstract sculpture, and a large family grave standing alone from the quiet graveyard.
While the big, touristed landmark temples are undeniably interesting to visit, it's when you watch residents praying or tending graves at the small local ones like this that you can get a better understanding of the place that temples hold in Japanese peoples' everyday lives.