Those that don't need to install files in Windows or add themselves to the registry might do so. It will depend on the program itself and how it's written. I recently installed a piece of DVD burning software that would do such but you aren't going to be able to run something from one OS that's been installed in another in the manner you desire.
I want to install software onto a portable external storage device so that I can run the software (database or server for example) from any laptop by just plugging it in through the USB port? The storage device would be like a netbook (with its own OS like XP) but without a display or keyboard. Just wondering if anything like this exits.

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