1. http://tech.groups.yahoo.com/group/nslu2-general/files/Plug%20Files
  2. Register to join the nslu2 Yahoo group.  It's quick and easy.
  3. Check out the plug.tar.gz file (read the comments provided for that file).  It's an archive that has all the important files ready to go.  It can save you a lot of time and work.
  4. You should also take a gander at the profile file they provide
  5. Once you follow the instructions on the Yahoo group installing rsync is as simple as
ipkg install rsync