I like the vi/vim cheat sheet.

The title link to the ministry of environmental protection of the PRC.

Here is anther aqi site.

BEUTLER INK gathered the biggest stories of the past year in to a picture.

It may be 2012 or 2013, I first found this website.

It seems that when thick fog and haze shrouded Beijing, these cameras stop work and the website provide us two night photo. Howerver it is 9:20 a.m. now.