First foray into asynch JS loading, this is a little snippet of the Surftourist maps code

ST.maps.coffee

class ST.maps.Map

  constructor: (el, title, opts) ->
    @el = $(el)
    @opts = $.extend true, {}, @defaults, opts
    if @el.length
      @title = title
      @markers = []

      # Load Google maps if it's not present
      if not google?.maps?
        # Dynamically create a callback method to continue this map's setup routine
        callback = "initMap#{@el.attr('id')}"
        window[callback] = (=>
          => @init()
        )()
        $('body').append """
                          <script src="http://maps.google.com/maps/api/js?sensor=false&callback=#{callback}"></script>
                         """
      else
        @init()


  # These functions set it up
  init: ->
    # But we're going to need some more stuff now, so load that up
    Modernizr.load
      test: InfoBox? and RickMarker?
      nope: '/assets/mapsExtra.js'
      complete: => 
        @setCenter()
        @makeMap()
        @processPoints()
        @addPoints()
        @infoWindows()
        @drawLine()
        @markCenter()
        @setBounds()

        # There may be external setup shiz that's listening
        $(document).trigger 'mapsLoaded.ST'