OK - here is the one that works on Mountain Lion.
- Go to http://osxfuse.github.com/
- Install FUSE for OS X
- Install SSHFS for OS X
- Then the following commands on your terminal:
mkdir /Volumes/SSHFS
/usr/local/bin/sshfs username@host:/path/to/dir /Volumes/SSHFS
Done.
I would also recommend using the ReMate plugin as pointed out by another user to prevent TextMate from beach-balling every time you refocus it. Link:
ReMate http://ciaranwal.sh/remate