MacFUSE is a framework for loading filesystem modules in userspace. This means that you need to install one kernel extension for all the supported filesystems (and there are a lot: sshfs, ftpfs, read/write NTFS, and more) and then load the modules for each filesystem as needed. This is a lot cleaner than having to load a different kernel extension for every filesystem and wondering whether they will cooperate with one another or figure out which one is crashing your Mac. The author of MacFUSE, Amit Singh, posts amazing things about Mac OS X internals at and is the author of Mac OS X Internals.