BuddyPress.org

Here’s an example – http://www.leckhamptononline.co.uk/category/videos/ . As @jivany says this is standard wp functionality. This pulls all the posts in with the category ‘video’ which i think is what you want to do. All you have to do then is hard code the url that calls the categories into your menu. I use the ‘page links to’ plugin to do this. It’s really easy.