Unique category filter per page

Hiya,

I have a site for a college library that I am working on. I have more than one page with blogs, set up using categories. What I would like to do is have a filter widget in the sidebar that lets users choose from a specific set of categories that will be different for each blog page. I have a lot of categories and using the standard widget is a bit unwieldy.

Thanks very much,

Nigel.