I guess I've got a little update to this thread, since I've stumbled upon a similarly priced and functioning setup.
Believe it or not, this rig centers around the Apple AirPort Express. I knew the Airport (I'm going to omit the double caps, I find that annoying) had analog output of music, using iTunes to control it - but I didn't know that with an adapter, it also has an optical output to send to the DAC of your choice.
So if all your files are mp3, aac, or alac, you're set to go - plug in your DAC and control with your computer. Or better yet, since we want remote capability with the PC in another room, an iPod Touch or iPhone can control iTunes.
But I know most of you - and me too - have your music as FLAC files. Well, iTunes can't play FLAC, of course. I don't like iTunes anyway, so that's not a big deal to me.
Luckily, there's actually a plug-in that will allow you to send the output from Winamp, MediaMonkey, or XMPlay to the Airport - it's not free, but at $10 (or $25 for unlimited upgrades) it's entirely reasonably priced:
http://emilles.dyndns.org/software/out_apx.html
Now, this wouldn't be any good without a way to control one of those remotely. But there's a $4 app for Winamp...
http://www.movingapps.com/
And a $6 app for MediaMonkey:
http://melloware.com/products/imonkey/
So, the total damage:
Apple AirPort Express: $99
Apple iPod Touch 8GB: $229
Remote Speakers Output Plug-In: $10
iAmpRemote or iMonkey: $4/$6
Total: $342 or $344 plus the cost of a DAC and TOSLINK cables and adapters.
Sounds good to me - and if you do it right, no one will even know what or where the source is! You could hide the Airport and DAC behind your stack.
There shouldn't be nearly as many - if any - issues with the software as with the Squeezebox, I would think. You also get a way cooler remote. I'm honestly not that big of an Apple fan, but let's face it - the Duet remote just isn't very well built, or versatile either.
All in all, it sounds like an even more robust system for streaming FLAC files, especially given the widespread support for both Winamp and the related Apple products.