tienhmdev

The “TINET Chat Buttons” displayes an fixed contact button on the bottom right of the screen. It opens an modal with your favorite contact form plugin. Before you have to generate a contact form and after this copy the shortcode into the plugin settings form Floating Contact Button. 
The plugin is real lightweight. The .css file is minimized to load as fast as can.
<h3>A brief Markdown Example</h3>
<pre><code><?php code(); // goes in backticks ?>
</code></pre>

TINET Chat Buttons

Thanks!

TINET.VN Chat Buttons is a free WordPress plugin for adding the live chat/call functionality of popular social media messaging apps.

strx

If you have a classic column site structure, this plugin will make your sidebar follow your visitors while they scroll up and down the page.
Try it <a href="http://www.strx.it" rel="nofollow ugc">Here</a> or <a href="http://www.sulmonte.org" rel="nofollow ugc">Here</a>
Increase ads earnings making them always visible to the user, even when writing a comment on bottom of pages. Let visitors click on sidebar links without having to go up, at the beginning of the page
See also: <a href="http://www.strx.it/2010/11/wordpress-floating-sidebar-plugin/" rel="nofollow ugc">Official Blog Post</a>

Strx Magic Floating Sidebar Maker

Magic Floating Sidebar Maker, makes your bog sidebar floatable.

TINET Chat Buttons vs Strx Magic Floating Sidebar Maker