- SysRescueCD (for an NTFS capable 'gparted') - http://www.sysresccd.org/Download
- rEFIt bootable CD (or install to hard disk, doesn't matter) - http://refit.sourceforge.net/doc/c1s5_burning.html
- Windows XP/Vista/7 CD (depends what you've installed) - just for a quick 'repair' at the end, no reinstall here!
- Shrink Mac partition in OSX's Disk Utility
- Grow the NTFS partition in gparted booting off sysrescue CD (reboot->option key). This may take 30mins to a few hours to complete!
- Boot the rEFIt CD -> choose "start partitioning tool" -> hit yes when it says it needs to sync the MBR with the GPT.
- Boot your Windows CD. Vista/Windows7 CD -> hit the repair option to fix the boot record. XP CD -> you may need to go to the administrative shell and type fixboot.
- Reboot and you should be able to boot into Windows via the option key as before. I liked rEFIt a lot so I installed it to my disk itself. (FYI, I did notice I needed to install rEFIt a few times to get it to show up during boot time)