Image by Dan Coulter via Flickr
If you're familiar with Google Labs this is a similar project which I feel makes sense to allow users to test features which aren't quite ready for prime time. There are five currently available which are definitely worth checking out -
Facebook Prototypes let us share the experimentation going on inside the walls of Facebook with the rest of the world. You'll be able to test any of the products and features we launch as Facebook Prototypes and then provide feedback directly to those of us who built them. To access Prototypes, visit the Application Directory and filter by "Prototypes." From there, you can activate or download any of the Prototypes listed.