A nice tutorial on setting up ssh to avoid password prompts also covers how you can restrict the commands allowed and setup a cron job to run rsync.

Karsten Thygesen has written a doc on how to setup anonymous rsync servers.

Jim Davis has written a doc on how to setup cfengine to use rsync.

Anthony Wesley has written a doc on how to build rsync for Windows95.

Mike McHenry has written up come info on how to get rsync working under NT.

Michael Holve has written a very useful rsync tutorial.

Daniel Teklu has a detailed HOWTO on rsync and stunnel.