MacRumors.com

CNet's Gadget blog had previously reported that Sling Media was working to get their SlingBox working with the Apple TV. A Sling Media employee confirms that this was accurate:

Yes, I can confirm this is accurate. (I work for Sling Media.) The Slingbox currently supports over 3,000 AV devices (cable boxes, DVRs, DVD players, etc) via IR and we’ve got many more in the pipeline. For Apple TV, you’d use the component pass-thru on a Slingbox Pro with HD Connect to remotely view, or listen, to your content. Our SlingPlayer software (computer and mobile) offers an audio-only mode, so we’re not just talking iTV video here… Select an iTunes playlist, switch to audio-only if you’d like (reducing bandwidth), and listen to your music anywhere you’ve got Internet.

SlingBox is media box that allows users to watch and control their home TV, DVR, or home theatre setup on a Mac or PC over the internet. CNet's Gadget blog also notes that Sling Media has been offering the ability to stream content to your mobile phone and speculates that Apple's iPhone support could be in the works.

This functionality would allow you to have your entire iTunes library available to you on your internet enabled phone (iPhone or not) without directly syncing your entire library to your phone.