With Amit Singh's release of MacFUSE at Macworld Expo 2007, the Mac now embraces a much broader array of file systems, improving cross-platform compatibility, network connectivity, security, and convenient integration with a variety of online services.
http://googlemac.blogspot.com/2007/01/taming-mac-os-x-file-systems.html
http://code.google.com/p/macfuse/
File Systems: Deep Magic -- As a general rule, accessing disks and managing files on them (via partitions and file systems) is considered 'low-level' operating system technology, and restricted from 'normal' users. In UNIX terms, file systems are superuser ('root') territory. With today's single-user systems, this can be more trouble than it's worth, especially since kernel programming is a great deal more demanding than writing normal ("user-space") programs. While Mac OS X and Linux offer multiple ways for users to work with file systems, they're still nowhere near as common or easy to develop as applications.
The FUSE ("Filesystem in USErspace") project was created to alleviate these problems on Linux. FUSE comes in two parts: a kernel module to handle the privileged operations, and a simple non-kernel API to host plug-in file system modules. FUSE/MacFUSE by itself does nothing -- it just provides the kernel plumbing for hosting file systems, and the simple API for its plugin modules. The assorted FUSE modules provide a wealth of options, including sshfs (allowing SFTP servers to be mounted directly on the desktop), NTFS (providing full read/write access to Windows partitions, as opposed to Tiger's built-in read-only NTFS support -- yes, this includes Boot Camp), and dozens of others.
http://fuse.sourceforge.net/
http://code.google.com/p/macfuse/wiki/FILESYSTEMS_TESTED
http://fuse.sourceforge.net/wiki/index.php/FileSystems
Warning: This is still very young beta software, so you shouldn't use MacFUSE unless you're prepared for problems -- meaning have 2 backups before you begin! That said, reports to date have been consistently positive.
The MacFUSE project provides a Mac kernel extension ('kext') instead of the Linux kernel module, and the same module API as its Linux cousin, so Mac users can take advantage of existing FUSE modules. In addition to the aforementioned sshfs & NTFS, available modules offer access to WebDAV & FTP servers, encrypted local partitions, ZFS, music on an iPod, iTunes & iPhoto shares, Flickr & GMail, wikis, blogs, etc. People are now actively testing existing FUSE modules for compatibility with MacFUSE.
To see MacFUSE in action, watch Amit's video demonstration.
http://video.google.com/videoplay?docid=3138515991250095768
MacFUSE has already generated a good deal of excitement, and at least two different efforts to provide a GUI. Hopefully it will be possible to use MacFUSE file systems from Apple's "Connect To Server" dialog, but Apple doesn't currently support this.
If you are intrigued by these capabilities but not ready to install beta kernel modules on your Mac, Interarchy may be a better option. Its "FTP Disk" technology with bidirectional synchronization allows it to simulate a MacFUSE-style file system mount for FTP, SFTP, and WebDAV (HTTP & HTTPS) servers.
Getting the Goods -- MacFUSE is very new, but it has already generated considerable interest. There are at least two projects to provide a graphical user interface (GUI) to manage MacFUSE and its file systems, and several people have stepped up to provide various distributions of the software. Currently, there are three main ways to get MacFUSE: Source, Binary, and Fink. Each of these provides MacFUSE itself and the sshfs filesystem plug-in. For other plug-ins, check the plug-in's homepage.
If you have Apple's Developer Tools installed, you can compile MacFUSE and sshfs yourself, with instructions on the MacFUSE site (including how to install NTFS-3g).
http://code.google.com/p/macfuse/wiki/HOWTO
If you don't want to compile, or don't have the Developer Tools, you can download a precompiled copy from the MacFUSE site instead (either as a Disk Image or as a 'tarball'). As of this writing, I haven't found a precompiled NTFS-3g plug-in.
http://code.google.com/p/macfuse/downloads/list
If you use the Fink package management system, you can get MacFUSE and sshfs with "fink install sshfs". If this doesn't work, make sure you have enabled the "unstable" Fink packages (The "Trees:" line in /sw/etc/fink.conf must contain "unstable/main") and updated Fink ("fink selfupdate; fink update fink"). As of this writing, Fink doesn't yet offer the NTFS-3g plug-in.