Bought (and returned) a Seagate FreeAgent GoFlex Ultra-Portable External Hard Drive, 500GB, yesterday and tried to use it on a public Mac but couldn't because I didn't have the "admin" password to install the required Mac-compatibility software (and can't get one).
I need to buy an ext. storage device that can work with my WinXP PC and be written to on this public Mac running OS X. Please suggest a Brand and Model that will work for this, I am at a loss.

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