NOTE: If you recently upgrade to Mountain Lion you probably need fix Homebrew + GCC
Change the /usr/local permission to yourself:
$ chown -R `whoami` /usr/local
Make sure you have a clean installation, if you had installed MacFuse before or you need uninstall it first:
$ sudo /Library/Filesystems/fusefs.fs/Support/uninstall-macfuse-core.sh
Also uninstall fuse4x and sshfs in case you did brew install:
$ brew uninstall fuse4x
$ brew uninstall sshfs
Remove garbage:
$ rm -rf /usr/local/include/fuse
$ rm /usr/local/lib/libfuse_*
$ sudo rm -rf /Library/Filesystems/fusefs.fs
$ sudo rm -rf /System/Library/Extensions/fuse4x.kext/
Try search for fuse and remove anything else left:
$ find / -name "*fuse*" -print
Alright! Time to start over:
$ brew install fuse4x
$ brew install sshfs
Make sure to follow the directions given by brew info fuse4x-kext before trying to use a FUSE-based filesystem.
$ brew info fuse4x-kext
$ sudo /bin/cp -rfX /usr/local/Cellar/fuse4x-kext/0.9.2/Library/Extensions/fuse4x.kext /Library/Extensions
$ sudo chmod +s /Library/Extensions/fuse4x.kext/Support/load_fuse4x
Run brew doctor to check if everything is ok and finally:
$ sshfs root@10.0.1.1:/var/www ~/Documents/mount