In this video, I explain a cool feature in SharePoint where you can connect 2 separate lists or document libraries via the Dynamic Filtering option. This will allow you to filter one list based on the selection in another list.
More about this topic
One of the greatest benefits of metadata is the ability to filter on it and get to what you want with just a few clicks. Filtering for information is quite a common exercise these days. Every time we do online shopping, we filter for stuff. When we shop on Amazon® for shoes (something I do every day :-) ), we filter on cost, shoe size, reviews, brand among other things. When you go to a bookstore website, you filter for author and genre.