====== Other Useful Web Applications ======
  * ref: http://www.oschina.net/news/16851/4-stackoverflow-like-opensource-systems
  * QnA web system:  
    * http://www.question2answer.org/
    * Qwench
    * Shapado
    * OSQA

====== Forum ======

  * Discourse: https://www.discourse.org/

====== Live Chat ======

  * Rocket.Chat: https://rocket.chat/
  * Let's Chat: https://sdelements.github.io/lets-chat/

====== Cloud File Server ======

  * Davros: https://github.com/mnutt/davros
  * ownCloud: https://owncloud.org/
  * SparkleShare: http://www.sparkleshare.org/
  * Pydio: https://pyd.io/
  * Seafile: https://www.seafile.com/

====== Code Manage ======

  *