Awesome.. I kept seeing these..
$249.. was just tooo much.
I installed the Netflix Windows 8 application and XBMC.
I then installed OblyTile and created a custom large button at the Start menu/tile interface for XBMC (needed to customize the tile with the XBMC logo, but wasn't tough). I also added the Netflix tile right next to it, large as well.
I installed Chrome (browser of choice) and created two smaller tiles that were links to bookmarks in Chrome, YouTube and Google Music.
Change the background of the Start/tile interface to something dark with a little bit of a pattern. Looks very clean and crisp.
I use a Logitech K400 right now. I have a Logitech 650 and Flirc I want to finish setting up, but I haven't had the chance to tinker with that aspect yet.
Overall, Windows 8.1 and XBMC + Netflix works really well. The Netflix app is stellar and XBMC keeping XBMC full screen (hitting "\") and just hitting the Windows button to get out of it/go to Netflix is very smooth and user friendly. I prefer it over the Apple TV and my Ouya by far.
And I built it with the very affordable [Intel NUC DN2820FYK](ark.intel.com/products/78953/Intel-NUC-Kit-DN2820FYK), which accepts 2.5" HDs.
The Harmony 650 works and is $60.