I have a comment regarding VirtualBox to run Windows apps in Linux with the 'coherence mode' you mentioned.
I just switched to openSUSE 11.1 when it came out, and have installed the latest VirtualBox version. I had a Vista Ultimate laying around (free from a seminar a year or so ago) so I grabbed it and installed it. Once you have Windows up and running, you install the 'guest additions' for VirtualBox. Then, when Windows is fully booted up and you have signed in you will have an option called 'seamless mode' available. This mode gives you the Windows start bar in Linux which can be docked on any side (even against your Linux task bar).
When you run a program from the Windows start bar it shows up as a running window in the Linux environment, and not stuck inside the confines of a guest VM's window. You can move them around and minimize them to the Windows bar. Pretty seamless if you ask me! :)
I have not yet tried installing WDSCi, but I can not imagine an instance where it would not work as it does on a native Windows system.
Even the performance is decent on my system with both OSes running. I've got a true dual-processor (two socket) 2.0GHz system w/ 2GB of PC2100 RAM. It's a little long in the proverbial tooth, but it seems to handle openSUSE 11.1 + Vista Ultimate (with performance-type settings) just fine!
You should give VirtualBox a try. It may be as close as we can get to having a native WDSCi on Linux for now. HTH.
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