"Currently Reading" Plugin for WPMU 2.7?

I'm looking for a simple plugin that would allow a widget in the sidebar to show thumbnails of books "currently being read"...ideally something that pulls thumbnail images from amazon.com. I've tried about 15-20 plugins so far and they are either too complicated for the average user or they're incompatible with WPMU 2.7.

Trying to give my users a simple way to show book covers in the sidebar basically.

Any suggestions?