here is the source
http://schen.s3.amazonaws.com/public/s3sync.tar.gz

this is no where near acceptable code quality, e.g. i disable Thread.critical logic which is broken by ruby 1.9
I just want to use this to sync files to my s3 bucket. and i'm not that good with linux to figure out how to install ruby 1.8. so i took couple of hours and did a really dirty hack to work with ruby 1.9
if you are in the same situation, feel free to give it a try. i'm not responsible for any damage.