The explore page offers a great snapshot. The search page is totally awesome too (seriously, it works really well) but only when you are looking for something in particular. It feels like there is a mind-boggling amount of potentially useful things sitting there that no one ever knows to play with because the people behind the projects aren't very good at PR or aren't looking for high usage of their product. I guess the main barrier to testing out projects/apps is the difficulty of installation. You have to know you want the product a lot to go through with the effort to get it up and going. I guess that's why recommendations can be a good guide to making sure it's worth the effort.