s3cmd
Amazon S3 is a reasonably priced data storage service. Ideal for off-site file backups, file archiving, web hosting and other data storage needs. It is generally more reliable than your regular web hosting for storing your files and images. Check out about Amazon S3 to find out more.
S3cmd is a free command line tool and client for uploading, retrieving and managing data in Amazon S3 and other cloud storage service providers that use the S3 protocol, such as Google Cloud Storage or DreamHost DreamObjects. It is best suited for power users who are familiar with command line programs. It is also ideal for batch scripts and automated backup to S3, triggered from cron, etc.
S3cmd is written in Python. It's an open source project available under GNU Public License v2 (GPLv2) and is free for both commercial and private use. You will only have to pay Amazon for using their storage.
see also s5cmd