I want to be able to run parallels on my Imac but i don't want to use up much space on my hard drive. but i do have an empty external hard drive at my disposal. i want to know if i can install and run parallels off of the external hard drive, and if i cant to that then at least install windows onto the external drive and run it through parallels. if either is possible or if anything close is possible then please either tell me how to step by step or post a link to instructions. I searched on my own and i couldn't find anything. Thank you all in advance.