Plex, a fork from the XBMC project, created a third party app for the Synology platform. Synology is known about the NAS devices and solutions.
The Plex app will install a media server service on the NAS device. Different systems like PC’s, iPhone’s and iPad’s should be then capable of streaming from the NAS directly. The Synology NAS will also feature it’s own website from where media can be watched or played.
Here’s an example:
More information can be found on: http://blog.synology.com/blog/?p=1012