As the title implies, I'd like to know if I can install windows 7 (possibly 8 later) on an external HDD and boot from there on my Mac? The thing is, for reasons out of my control, I can't get a (legal) copy of Parallels. As far as BootCamp goes, let's just say I would rather use it only as a last resource, as I would rather not partition my main drive. How plausible would it be to load up the OS from an external HDD and have my Mac's full power? (all cores, RAM) I know PCs can just boot from any drive, provided it has an OS installed, but I'm new to Macs, so I have no idea if the same can be done.