I have what I tried below, but I eventually dropped the attempt. The Lenovo modules hung up VMWare any time I tried to boot it that way, and while I could mount the NTFS partition used by WinXP R/W with the tools below, I could not easily get WinXP to look at the lion's share of the drive. (My fault, really – if I weren't so attached to other filesystem types, I could probably have made this work).
My new-fangled laptop comes with XP Pro, and I don't have disks for re-installing that OS from scratch (in VMWare, for example). So, as an experiment, I decided to resize the WinXP partition, and put gentoo on the lion's share of the drive. I want to see if I can get a dual-boot OR VMWare image running off of that same base – because I think that would be cool1. File access would be interesting – but that's another story; I want to see if it will work, first. As part of that effort, I also added support for R/W NTFS2.
While poking around, I read up on NTFS3 – and I think, based on the interoperability section, that I'll also look into ntfs-3g. Note that this requires the freshest version of fuse, which means: don't compile CONFIG_FUSE_FS into your kernel. Either compile it as a module, or leave it out entirely.
Footnotes / References :
3 NTFS :wiki: