The developper of SkyOS (a commercial OS developped from scratch with the BeOS Spirit but based on their own new kernel and own GUI) Darkness has createda software called SkyFS/BFS viewer. As this name tells by itself, it provides you to view and copy your SkyFS (of course) but also BFS from Windows !



Actually, this software is not working under Windows XP but Win95/98. It also can copy a file from SkyFS and BFS to your Windows disk, but not the other way.
You should probably not know it, but a BFS driver is available for Linux since 1999, coded by Makoto Kato, but never release as stable. Will Dyson has done his own in 2001(more infos available here)

And for your eyes pleasure only: SkyOS 1, SkyOS 2, SkyOS 3 and SkyOS 4.