ldr_replace_imageurl.user.js

// ==UserScript==
// @name           LDR filters
// @namespace      http://d.hatena.ne.jp/Constellation/
// @description    replace image URL, and so on.
// @include        http://fastladder.com/reader/
// @include        http://reader.livedoor.com/reader/
// ==/UserScript==

(function(win){
  var image_check = /(?:\.jpg|\.png|\.bmp)$/
  win.register_hook('BEFORE_PRINTFEED', function(feed){
    feed.items.forEach(function(item){
      if(image_check.test(item.link)){
        item.body = '<img src="'+item.link+'" />';
      }
    });
  });
})(this.unsafeWindow || this);