Content Drop Down Filter Plug-in

I am looking for a plugin that will allow users to filter content (PDF files, videos, Powerpoint) on my site using three drop down lists
Industry
Solution
File Type

The files could belong to more than one category under each drop down list.
Once a user makes the selection I want all linked thumbnails of all relevant files to appear underneath the drop downs.

I am looking for something similar to the functionality found on these two sites:

Case Study Drop Down Filters
http://www.alfresco.com/customers

Customer List
http://www.marketo.com/customers?Industry=software-and-cloud

Does anyone have any recommendations?

Thanks.