The Random Featured Post plugin allows you to display a random post from a designated category. Ideally this should 
draw readers landing on your homepage to some of your best posts. The featured post will display the title 
“Featured Post” (customizable) along with the post’s title, an excerpt and a link to continue to the full post.
<h3>Additional Notes</h3>
<ul>
<li>The show_featured_post($PreFeature = ”, $PostFeature = ”, $AlwaysShow = false, $categoryID = 0, $NumberOfPosts = 0) function has five optional arguments. 
The first two are for any HTML you would like to display before and after the featured post. The third argument is a 
boolean (true/false) argument which will override the \’Show Featured Post\’ option and always display the featured post when true. The fourth option allows you to 
specify a single category to display from, overriding the selections in settings page. The fifth option allows you to show more than one post at a time, overriding 
the settings page option.</li>
<li>All output is contained in a DIV class named “featuredpost” and can be adjusted via your stylesheet.</li>
</ul>

Random Featured Post

The Random Featured Post plugin allows you to display a random post from a designated category as a "featured" post.

mrzerog

WP Favorites allows your logged in users to favorite a tag, and allows them to see only posts that have that tag. They can also favorite multiple tags, and see only posts that have all those tags (or optionally any post with any of those tags). Example: You run a site about tea, iced and hot, green black and white. You tag every post green, black, or white, as well as iced or hot. Your user only likes iced green tea, so they favorite the ‘iced’ tag, and the ‘green’ tag. Then, they can see only posts pertaining to iced green tea (or optionally any post’s tagged either iced or green). Users are able to favorite a tag from it’s archive page.

wp_favorites

wp_favorites allows a logged in user to favorite a tag or tags and then show only posts that have that tag or a combination of those tags

Random Featured Post vs wp_favorites