best (free) way to recover data on a corrupt ntfs hdd?

I have a 250 gb external drive that will not mount in mac os (using macFUSE) or in windows. It is ntfs formatted, and I’m looking for decent freeware or just a simple way to get my data back/get the disk to work again.

(under winxp I get the message that the directory is “corrupted and unreadable”)

Also – a google search only returns several pages of shareware / demos – I’m hoping there’s an easier fix than that.