Joost de Valk

Easily add breadcrumbs to your template. If you’re using one of the supported WordPress frameworks, it’s as easy as enabling the plugin and checking the “Try to add automatically box”, if you’re not using one of those, adding it is as simple as adding one line of code to your template!
<h4>Supported Frameworks</h4>
Currently the breadcrumbs plugin supports the following frameworks:
<ul>
<li>Thematic</li>
<li>Hybrid</li>
<li>Thesis</li>
<li>WP Framework</li>
</ul>
More info:
<ul>
<li><a href="http://yoast.com/wordpress/breadcrumbs/" rel="nofollow ugc">Yoast Breadcrumbs</a>.</li>
<li>Read more about how to improve your <a href="http://yoast.com/articles/wordpress-seo/" rel="nofollow ugc">WordPress SEO</a>, so you can get the most out of this plugin.</li>
<li>Check out the other <a href="http://yoast.com/wordpress/" rel="nofollow ugc">WordPress plugins</a> by the same author.</li>
</ul>

Yoast Breadcrumbs

viperchill

ViperFeed adds a gorgeous footer to your RSS feed. This will be displayed for people who get your blog posts via email, or in an RSS reader like Google Reader and Bloglines. You can use this space for giveaways, encouraging comments, showing ads, or linking to other areas of your website.
<a href="http://www.viperchill.com/" rel="nofollow ugc">ViperChill</a>, a blog on Viral Marketing, is the creator of this plugin. If you want to take your blog to the next level, you should read this post on <a href="http://www.viperchill.com/wordpress-seo/" rel="nofollow ugc">WordPress SEO</a>.

ViperFeed

ViperFeed adds a gorgeous footer to your RSS feed. This will be displayed for people who get your blog posts via email, or in an RSS reader.

Yoast Breadcrumbs vs ViperFeed