GF 3.1.6 released 23 April 2010.
gf-3.1.6-leopard.pkg (7.7MB)
gf-3.1.6-bin-intel-mac.gz (1.9MB)
gf-3.1.6-bin-i486-windows.zip
  (1.6 MB)
gf-3.1.6-bin-i486-linux.gz
  (1.7 MB)
gf-3.1.6-lib.tar.gz
  (4.4 MB)
gf-3.1.6-src.tar.gz
  (11 MB)
GF is also on Hackage
What's new? See the release notes.
The Windows package is installed by just unpacking it anywhere. 
It finds the libraries relative to the .exe file.
To install a binary package for MacOS X or Linux: uncompress the executable and
put it somewhere on your path, renaming it to just gf. For instance:
    gunzip gf-bin-[version].gz
    sudo mv gf-bin-[version] /usr/local/bin/gf
To install the libraries (if done separately), unpack them in the place to which your
GF_LIB_PATH points.
    cd $GF_LIB_PATH
    gtar xvfz gf-lib-[VERSION].tgz
If this variable hasn't been defined, it is useful define it, e.g.
    export GF_LIB_PATH=/usr/local/lib/gf/
To compile and install from source on Mac or Linux, do:
    tar xvfz gf-[VERSION].tgz
    cd GF/src
    runghc Setup configure --user
    runghc Setup build
    runghc Setup install
The last command must be prefixed by sudo, if the installation is outside
user-writeable area.