well - not quite...

Linuxcnc has had the capability to run Ethercat directly for a while now. 

http://wiki.linuxcnc.org/cgi-bin/wiki.pl?EtherCatDriver

PC's are certainly suitable for realtime determinism.  (and you can do it cheaply) with the right OS.

https://www.youtube.com/watch?v=7kn-G5HFjD8

EtherCat Master is a realtime system, PCs are unsuitable as is and the solutions to achieve realtime determinism are just to expensive
for me to get into as a hobby project.

Craig

Uh...  we were talking about Windows.  

Hi,
yes, sorry I was meaning Windows when I actually said PC.

I am impressed that Linux is realtime capable.

Craig