So you have Boot Camp and a big disk to use, but then you are bound to the NTFS format instead of FAT. But Mac OS X 10.4 can only read, not write, to these kind of formatted volumes. Follow these steps and you will be able to write to them as well:
- If you choose to compile yourself, install Xcode 2.4.1, and especially the SDK package within it. Also, compile the latest release of pkgconfig.
- Download MacFuse. Compile it yourself, or easier of course, is to download the binary .dmg file.
- Download ntfs-3g and compile it -- there's also a premade binary .dmg if you prefer.
- In Disk Utility, check out the device identifier (disk0s2 or something) of the NTFS volume, and unmount it.
- In Terminal, type mkdir /Volumes/your_ntfs_volume, where your_ntfs_volume is the name of your NTFS volume.
- Still in Terminal, type ntfs-3g /dev/disk0s2 /Volumes/your_ntfs_volume -o ping_diskarb,volname="your_ntfs_volume".
[robg adds: I haven't tested this one, and would caution that if you plan to test it, you have a good backup before you begin.]

