AngularJS & Rails

app.js

/**
 * Angular needs to send the Rails CSRF token with each post request.
 * 
 * Here we get the token from the meta tags (make sure <%= csrf_meta_tags %>
 * is present in your layout.)
 */
angular.module('myapp',[]).
  // configure our http requests to include the Rails CSRF token
  config(["$httpProvider", function(p) {
  var m = document.getElementsByTagName('meta');
  for (var i in m) {
    if (m[i].name == 'csrf-token') {
      p.defaults.headers.common['X-CSRF-Token'] = m[i].content;
      break;
    }
  }
}]);

production.rb

MyApp::Application.configure do |config|
  # Don't mangle Angular's special variable names!                                                                                                                                                                                        
  config.assets.js_compressor = Sprockets::LazyCompressor.new { Uglifier.new(:mangle => false) } 
end

Not one, but two useful things I found here! Thanks.

You could just do this to get the token so that you don't need to loop through the whole thing:

$('meta[name="csrf-token"]').attr('content')

Also you probably want to set the 'Accept' header to application/json

Can also sniff the DOM the angular way if you're not using jQuery.
angular.element( document.querySelectorAll('meta[name=csrf-token]') ).attr('content')