Sibin Grasic

Responsive Videos plugin will allow you to automatically resize and scale your embedded videos on mobile devices. 
CSS selector option is provided so you can target only your post / page content container.
Features
<ul>
<li>Automatic configuration option</li>
<li>Automatically resizes / scales all your embedded videos</li>
<li>Works on all browsers</li>
<li>Highly compatible – you can change the css selector for the text highlight</li>
<li>Customizable – you can select the page type on which to activate the fitVids script</li>
</ul>

Responsive videos – Fitvids

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Make your Embedded videos responsive on mobile devices with jQuery FitVids plugin

rfair404

FitVids
FitVids automatically sizes videos in responsive themes so that the video is always the right size.
Currently supports:
<ul>
<li>Videos in single posts</li>
<li>Videos on the homepage</li>
<li>Videos in archives</li>
<li>Videos in the sidebar widgets</li>
</ul>
FitText
FitText automatically sizes text responsive themes so that the text is always the right size.
Currently supports:
<ul>
<li>Site Title</li>
<li>Site Description</li>
<li>Single post titles </li>
<li>Post titles on the homepage</li>
<li>Post titles in archives</li>
</ul>
Lettering
Lettering automatically wraps text with tags so that each element can be styled, creating unique layouts.
Currently supports:
<ul>
<li>Spans around each letter</li>
<li>Spans around each word</li>
<li>Spans around each line</li>
<li>Advanced – Span around each word, and each letter within</li>
</ul>
<h3>Credits</h3>
FitVids.js
<ul>
<li>Copyright 2011, Chris Coyier – http://css-tricks.com + Dave Rupert – http://daverupert.com</li>
<li>Credit to Thierry Koblentz – http://www.alistapart.com/articles/creating-intrinsic-ratios-for-video/</li>
</ul>
FitText.js
<ul>
<li>Copyright 2011, Dave Rupert http://daverupert.com</li>
</ul>
Lettering.js
<ul>
<li>Copyright 2010, Dave Rupert http://daverupert.com</li>
<li>Thanks to Paul Irish – http://paulirish.com – for the feedback.</li>
</ul>

FitVids, FitText and Lettering (Oh My!)

FitVids, FitText and Lettering for WordPress incorporates the fitvids.js, fittext.js and lettering.js scripts into your site.

Responsive videos – Fitvids vs FitVids, FitText and Lettering (Oh My!)