>However, the class isn't instantiable, so using self won't work.

Sure it will. 'self' just refers to the current context, in either case
whether class or module that's what it is. So it should work fine.

> (you can call methods of a module without mixing it in right?)

Yes, if they are "module methods" as opposed to instance methods.
Modules methods, (also called class methods but usually in the context
of class) are singleton methods, or adhoc methods (my new prefered
term). You can tell this by the way they are defined --the name of the
object proceeds the method name in the def statement (eg. 'def
ImageBob.get_blob'). Another way to write them:

  module ImageBlob

    class << self  # opens adhoc context

      def get_blob
         ...
      end

    end

  end


T.