Recommended and introduced by Trevor [here](http://www.hackingchinese.com/extensive-listening-challenge-october-2014-wrapping-up/#comment-646686). Each book (one for each level of the new HSK ex... Read more.

amazon.com

This site is best described as a Chinese version of Quora, so in other words a site where people ask and answer questions (and discuss other people's questions and answers). Read more.

zhihu.com

This is probably one of the best resources for upper-intermediate or advanced learners of Chinese who want to learn something using their Chinese. Khan Academy has hundreds of videos about differen... Read more.

youtube.com

This website offers a large number of previous HSK and YCT Chinese proficiency tests, sorted by year and level. This is excellent for test preparation and/or benchmarking. Read more.

chinesetest.cn

Foreigncy provides daily digital flashcards, with audio, that prepare a user to read a foreign policy or economics from a regional source. The site also provide users with an English language summa... Read more.

foreigncy.org

This blog post contains both a list of most of the elements in the periodic table in both Chinese and English, but more importantly, it contains a discussion about the characters used to represent ... Read more.

languagelog.ldc.upenn.edu