Bergamini

Video Converter
Adds a link under the video embedded that allows to download or convert video to mp3. It supports Youtube and Vimeo at the moment but other portals like, DailyMotion, Facebook, Instagram will be added soon.
Supported WordPress youtube plugins
Currently these are a number of Youtube WordPress plugins that we support:
<ul>
<li>Default WordPress behavior without any wordpress plugin (mediaelements.js is not supported yet)</li>
<li>Smart YouTube PRO</li>
<li>Viper’s Video Quicktags</li>
<li>YouTube Embed</li>
</ul>
Supported Sources:
3sat, 8tracks, Archive.org, ARD, Arte.tv, AUEngine, Bandcamp, blip.tv, Break, Brightcove, CollegeHumor, ComedyCentral, CSpan, Dailymotion, DepositFiles, Dotsub, Escapist, Facebook, Flickr, FunnyOrDie, GameSpot, Gametrailers, Generic, HotNewHipHop, Howcast, Hypem, Ina, InfoQ, Instagram, Jukebox, Justin.tv, Keek, Liveleak, Metacafe, Mixcloud, MTV, MySpass, Myvideo, NBA, Photobucket, Plus-Google, RBMA Radio, RBMARadio, Soundcloud, Spiegel, Stanford OC, Statigram, Steam, Teamcoco, TED, TF1, TrailerAddict, Tudou, Tumblr, Tutv, ustream, Veoh, Vevo, Google Video, Vimeo, Vine, Wat.tv, Wimp, WorldStarHipHop, Yahoo, Youtube, Youku, ZDF
If you are using a youtube plugin that’s not supported please contact us and we will build support for it.
If you have any problems or suggestion please don’t hesitate and contact us on info@speeddownloader.com
Options include:
<ul>
<li>Customize appearance of link with custom css class</li>
<li>Customize the link text</li>
<li>Set the position of the link</li>
<li>Set the plugin to run on only on certain blog-post categories</li>
</ul>

Video Converter

Simple but it works

This Plugin Adds a link under embedded video's that allows to download or convert the video to mp3.

Justin Tadlock

Corey Snow

Audio Player Widget is a small plugin that provides support for using the Audio-Player plugin in WordPress sidebars.
The Audio Player Widget requires Martin Laine’s WordPress Audio Player plugin.
<ul>
<li>Homepage for Audio Player: http://wpaudioplayer.com/.</li>
<li>WordPress Plugin Page for Audio Player: https://wordpress.org/extend/plugins/audio-player/</li>
</ul>
Using the Audio Player Widget is simple. If your theme supports widgets and you have the Audio Player plugin 
installed, you can drag the widget to the sidebar and specify a label and URL for an MP3 file. The widget 
will render the Audio Player in the sidebar when the page is loaded by dynamically generating the [audio:URL] tag 
the Audio Player plugin requires.

Audio Player Widget

Audio Player Widget is a small plugin that provides support for using the Audio-Player plugin in WordPress sidebars.

Video Converter vs Audio Player Widget