Hi Brad
You may use any versioning tool and backup the project in that tool end of everyday (or earlier if required). You may send the project zip or the whole project as unzipped folders to the tool of your choice (Perforce, GIT etc).
You may use the services in MII to automate this process.
http://<server>:<port>/XMII/Illuminator?service=Transport&Mode=ExportProject&Name=<projectName>
Regards
Partha