git-annex has recently been ported to Windows.

This port is in an alpha state; many things will not work. See
[[todo/windows_support]] for current status. Note especially that
git-annex always uses [[direct_mode]] on Windows.

To build git-annex from source on Windows, you need to install
the Haskell Platform and Cygwin. When installing Cygwin, select
to install gcc, make, rsync, and ssh. Then, within Cygwin, git-annex
can be compiled following the instructions for [[using cabal|cabal]].