I've made a Freebookapalooza widget featuring British and Celtic books. You can see the script in action in the sidebar, and also below. Each item contains a link to the corresponding blog post at this blog so that you can find out more! :-)
I made these widgets with Randy Hoyt's wonderful RotateContent.com.
Here is the 200-pixel-wide version (good for blog sidebars):
And here is the 400-pixel-wide version: