Hi All, I have a 17" UMBP and would like to run Windows via either Fusions or Parallels. I prefer to keep the UMBP hard drive fully OSX so that way there is no way anything from Windows can affect the drive. I would like to ask then, if it would be possible to run Windows from an external hard drive? I have a spare Western Digital 250GB Passport that I am hoping I could use for this purpose. Thank You, Bazzy!