Word Lens is one of those apps I show people to blow their mind at where technology is up to these days.

It's a serious "we're in the future" moment every time I use it.

also bing translator for windows phone and PC: http://www.bing.com/translator/phone/

I remember seeing that app back in 2010. I hope they will do Chinese -> English and vice versa versions!

Word Lens doesn't do Japanese though.