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.

Your feed, on steroids : add a custom footer to RSS items with, for example, a copyright notice, a “Read More (400 words)” links, an “Add to del.icio.us” link, a list of related entries, or anything really (even custom PHP functions). Compatible with Feedburner or similar services.
Improve connectivity between your feed and your site !!
For documentation and tips, please refer to the official plugin page for <a href="http://planetozh.com/blog/my-projects/wordpress-plugin-better-feed-rss/" title="Better Feed" rel="nofollow ugc">Better Feed</a>

Ozh' Better Feed

Your feed, on steroids : add a custom footer to RSS items with, for example, a copyright notice, a "Read More (400 words)" links, an "A …

ViperFeed vs Ozh' Better Feed