WordPress.org

Display "Badges" in the side-panel which points to a web-site and an image which is then used to build the "badge". Using the Widget you can choose whether to:

1. (Optionally) display a Title
2. Link to a site
3. Required link to an image to mark that site (any size will work, but the "standard" seems to be 88 pixels wide by 31 pixels high)
4. Pad the Badge (including centering the text); some people may prefer using their own CSS, so this is an optional configuration.
5. Enable "Display Badge in a Box" (enabled by default)
6. Enable the Displaying of a Drop-Shadow

If more control is needed, or more badges need to be displayed, the badges plugin on the WordPress site might be a better fit.