s3mysqldump is a tool to dump mysql tables to S3, so they can be consumed by Elastic MapReduce, etc.
From source:
python setup.py install
The following command dumps 'user' table in 'db' database to s3 bucket s3://emr-storage/. 'my.cnf' specifies mysql parameters. 'boto.cfg' is the configure file for s3 connection which specifies things like aws credentials etc.
s3mysqldump -v --force -m my.cnf -s -b boto.cfg db user s3://emr-storage/user.sql