redwerks

This plugin allows posts and pages to have individual custom backgrounds. A full-body background that shows up on the post page itself can be specified. As well as background that just covers the content area and shows up on all places the post is visible.

Post Backgrounds

Allows posts and pages to have individual custom backgrounds. Both as body backgrounds and as content backgrounds.

swedish boy

A simple and powerful plugin to control your WordPress site’s background. The plugin changes background color/image of the tag. The plugin comes with a butil-in image uploading script. 
So your background images live inside the plugin and you don’t have to use WordPress “media handler”.
Features:
<ul>
<li>Image uploading</li>
<li>Archive with unlimited images</li>
<li>Url/link background image</li>
<li>Full CSS-control (repeat, fixed, positioning)</li>
<li>Color validation of hex-color values set to background-color.</li>
</ul>

Background Control

Control your wordpress site's background. With built in uploading of images.

Post Backgrounds vs Background Control