Formatting External Hard Drive?

I have an Iomega 500gb External Hard Drive. It’s currently formatted as NTFS, and works fine, but I’m trying to hook

it up to my Playstation 3 and it needs to be Fat32 format. Is it possible to do this without erasing everything on my

hard drive, and still leaving it compatible with my PC as well? Not sure if it matters, but I’m running Windows Vista,

and the most updated PS3 firmware.