https://docs.google.com/document/d/1X9RrbkUpiTQ-S6Acken-5fv7...
AMD fanless barbone w/ dual NIC (Jetway $215) http://www.newegg.com/Product/Product.aspx?Item=N82E16856107...
SSD 64GB ($62 sandisk) http://www.newegg.com/Product/Product.aspx?Item=9SIA4UB22Z51...
4GB RAM (no ECC) ($38 gskill) http://www.newegg.com/Product/Product.aspx?Item=N82E16820231...
So, $315 and ~15W max. I bet this could serve a small office well. Someone should get this down to $200 with minimal specs (and no video or audio).
It has dual Realtek NICs; it runs pfsense and openVPN well, and you can also run squid and snort if you're into it (I haven't learned how to use them yet, but I plan to).
The only downside is it uses Realtek NICs instead of Intel ones. Otherwise it's pretty much perfect.
1: https://www.globalscaletechnologies.com/t-dreamplugdetails.a...
https://www.globalscaletechnologies.com/c-14-gtimirabox.aspx