Grab a screenshot of Chrome using Chrome Developer Tools?

Chrome Remote Debugging Protocol now supports the Page.captureScreenshot function

Here is an example in coffee-script

screenshot: (name, callback)=>
    safeName = name.replace(/[^()^a-z0-9._-]/gi, '_') + ".png"
    png_File = "./_screenshots".append_To_Process_Cwd_Path().folder_Create()
                               .path_Combine(safeName)

    @chrome._chrome.Page.captureScreenshot (err, image)->
      require('fs').writeFile png_File, image.data, 'base64',(err)->
         callback()

(snippet from https://github.com/TeamMentor/TM_4_0_Design/blob/Issue_80_Jade_Cleanup/QA/API/QA-TM_4_0_Design.coffee#L54)