Never been, but I hear they (some of them?) go nuts when Westerners try to speak Japanese to them. I'm sure some of them don't appreciate it much (us going there and not knowing the language and having to be helped) and I'm sure it depends on where you are (Tokyo getting more international travelers; the further out spots, not so much). But I've heard a little respect goes a long way. They see your skin colour and they wonder what to expect, and you do a half decent bow and say 'konnichiwa' (hello/good day) passably, and end with a passable 'arigatou' (thank you), I hear they love seeing it, the effort to attempt their language.

I can't read the symbols worth anything, but I can say about three dozen words in Japanese. Can't string together too many sentences though. I feel like I'd be saying 'gomenasai' (sorry), 'baka desu' (I'm an idiot; lit. "this idiot") a lot — and possibly catching some laughs.