The Noto font for CJK languages
The Noto fonts have superseded the Droid fonts, which were originally designed for the use in Google's Android. Noto's aim is to be a free for everyone, with beautiful glyphs for all languages, looking good especially when multiple styles and weights and even languages are mixed on a page.
This package supports Japanese, Korean and simple/traditional Chinese.
Included are various weights and two 'monospaced' typefaces ('regular' and 'bold').