Welcome to gsbackup.org.
gsbackup is a web application (and shell script) written to make backups simple on the (gs) Grid-Service. The (gs) Grid-Service is (mt) Media Temple's popular web hosting platform This tool is not provided or officially supported by (mt) Media Temple, but was written by someone with extensive knowledge of the system.
gsbackup is 100% free to use (not counting any fees associated with Amazon's S3 service), and is an open source software (specific license TBD). The tool was written by Matthew Bell.
The code is also available at GitHub.