The finder component, with its perfectly intuitive API, is easily one of my favorite Symfony offerings. When you need to fetch a set of files or directories, based upon file type, creation date, file contents, and more, this component is definitely up for the job.
Laravel heavily leverages Symfony's event dispatcher component. This component is a perfect fit for the situations when you want to decouple your code, make an announcement to the rest of your application, and then respond to that announcement in any number of ways.
*Series still in development. Check back often for updates.