The OS/C extended filesystem designed specifically for the OS/C operating system. It closely mimics the Linux ext2 filesystem, and has the same general "tree" topology. Instead of utilizing a file allocation table like FAT, it uses a tree of inodes, or (in C) a single structure. The source code is not yet out, but it's getting there. It'll be mainly bug-free and ready for unveiling to the public some time very soon.