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.

Themepoints

WooCommerce Sales Counter Plugin For WordPress.

Sales Counter For WooCommerce

WooCommerce Sales Counter Plugin For WordPress.

Strx Magic Floating Sidebar Maker vs Sales Counter For WooCommerce