There's a few ways to go about that, but none I think are ready for
prime time yet.

Others may have more current input as it's been a while since I've looked
at this last but I didn't find a way to do this that I thought made any
sense.

There are solutions for all the mainstream platforms- doze, apple
and linux. All, in my opinion, require inordinate amounts of hardware,
specialized software and complicated setup to deploy.

In my world, what I'd like to see (and will probably end up with) is a
simple, small form factor PC that will display/play media files via
ethernet from a fileserver elsewhere in the house.

Instead what you see are boxes that try to do everything from serve up
media files to netflix movies to internet radio, and none do everything
well. I don't want all that crap (as I don't have broadband anyway).
I just want a simple interface I can control with a remote through my TV
to look at photos, play video files and DVD's, and listen to MP3's.
Seems simple, but the solutions I've seen to date either can't handle
certain file formats or you need a $1000 PC sitting next to your TV and
a high horsepower server to do it.

If someone's come up with a simple solution I'd sure like to see it.
Right now I'm using an old laptop hooked up to the TV (SVGA) running
Windoze (since it's too much of a PITA to get linux to play different
video formats) connected to my linux file server. The only thing missing
there is the "simple" IR control through the TV.

I'm keeping my eye on MythTV, which is the closest I'm seeing to a simple
set top box that can connect to a fileserver but looks like an awful PITA
to set up the back end. I'm looking for something the equivalent of your
typical consumer peripheral that you take out of a box, turn on and use.
Compared to a few years ago things have gotten a lot better but it's not
there yet.

As a side note, I came up to speed on all this a couple years ago when
I remodeled my house, and ran half a mile of Cat6 everywhere in
anticipation of having a media center and being able to serve up
anything, anywhere in the house. Still looking for the best solution
to take advantage of that infrastructure.