I released a command-line tool today, zenpush. It allows us to edit our knowledge base in markdown, and keep a copy locally.
Future releases could include support for images, or the synchronization of a complete forum or category.
PS - We have this workflow: markdown files are stored in a private git repository. All the team members can review and work together on entries before they are published. When I say "all team members", I mean *everyone*, even non developers can learn markdown in 15 minutes. Mou is their new toy http://mouapp.com/ . Once an entry is ready, it is pushed thanks to zenpush.