What's a Media Server? You may consider your Apple TV a media server, but it's more of a media streamer, since it lacks any storage capacity and can only feed material stored on your computer or direct from the internet via WiFi. But there are plenty of devices with a plentitude of local storage and connection options for your home theater and audio setups...


Entry Level: Logitech Squeezebox Touch, $300
This device delivers on all fronts, we like that is pretty easy to use and can integrate itself into an AV system with totally reliable playback of digital audio files and endless supply of internet content. Decodes MP3, FLAC, WAV, AIFF, Apple Lossless, MWA Lossless, APE, AMC. Connects thru ethernet and WiFi and it has a user friendly touch interface and internet radio support. As an added bonus, it comes with built-in Facebook and Flickr.


Midrange: Arris Moxi HD DVR, $499
The only drawback that we found on this device is the lack of accessing on-demand or PPV content; but other than that, this device is superior to the competition in every single aspect. It has scalable storage and some user interface that came straight from the future. This is a Media Server that surprise us in any way; and we have no doubt that will continue to evolve. HDMI output, serves 1080p and decodes Dolby Digital Plus. The standard hard drive is 500 gigabytes.


Budget Hi End: Sonos Bundle 250, $999
The press release states "The wireless that works like magic" and we think that they are not lying. Sonos is the real Mc Coy with a no hassle and a nice integrated way of controlling and accessing your digital library thru your entire house without the pain of running wires all over the place. Pandora, Internet Radio and other sources are supported too. The bundle includes a ZonePlayer 90, ZonePlayer 120 and the touchscreen Controller 200. iPads, iPhones and iPod Touches could be used as an additional controllers with the addition of a free app. This one is the best of the bunch.

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Apple TV may not be a server but the computer it streams from can be setup as a server. I use an old laptop with my movies in Itunes stored on a hard drive connected to an Airport Extreme. This system works great!
@emkiser Do you have your music stored on the same harddrive or are you pointing them to different places? I'm thinking about doing something similar with a Synology NAS but not sure how to deal with the fact that my laptop is my main computer and thus want some files on there and some on the NAS. Can you split up iTunes' folders so you can have the music on the laptop but the movies on the NAS?
i can't figure out how to stream media on NAS drive to my mac mini. for some reason itunes won't allow it
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My movies are on the external hard drive. My music is on the laptops hard drive. To do this I toggle the "copy files to itunes library when adding to library" on the advance tab. When importing movies, I toggle this off, copy my movie to the external hard drive and import the file from the external hard drive to my library. FYI you cannot sync these to an iphone unless they are on the computer's hard drive. I have a different laptop that I keep my music on for syncing with my iphone.
Not sure the Logitech is a server. Looks like a streamer to me.
Personally, I think getting a Mac Mini to use as a media server is the way to go.
Plex (plexapp.com) is also a very good alternative. I use it with a Mac Mini connected to a HDTV and ReadyNas and it just works!
I agree with @WhereWeveBeen. Plex is great, just like Boxee and other XBMC derivatives. The advantage of Plex over the other XBMC distros is that it actually has media server functionality, not just streaming.