All versions of Mac OS X, at least past 10.2, can read NTFS. USB, Firewire, network drive, doesn’t matter…

According to Wikipedia, it supports HFS+ (default), HFS, UFS, AFP, ISO 9660, FAT, UDF, NFS, SMBFS, NTFS (read only), FTP, WebDAV, ZFS (experimental). Snow Leopard, assuming you re-install the boot camp drivers, allows your Windows OS to read HFS+ via the said boot camp drivers….

So even two way access is allowed…