Everyone's favourite perpetual beta operating system, SkyOS, has introduced a concept of an interesting new feature, whose inspiration came from a feature on the Playstation 3. The feature is kind of like an always-accessible (even during the boot process) version of Front Row, which you can access using a mouse gesture or a shortcut. It then allows you to access and play all your media files. "So whenever you want to quickly listen to music you don't have to open a dedicated music player. Simply enter crossbar, select your song and return to the desktop. Crossbar has been designed to make this as fast and as straight forward as possible." Click read more for a video.
The video shows Crossbar running on an old P4 2.0 Ghz, no hardware acceleration (VESA only), with the interface ready in 10msec after pressing the shortcut. It currently supports images, music, videos, and web streams.
With such a feature, you have instant access to all your media, in a way that doesn't clutter up the desktop, and you don't have to load dedicate music/video players. The fact that this feature is available even in a pre-boot environment opens a whole can of abilities; for instance, I can easily see this being used to set up a locked-down kiosk-like multimedia interface.