auto save possibilities?

Thought I'd start here in one of my favorite haunts, the Interactive Tools Forum...

A client is using the Add Apply Button plug-in, but would like to explore a more automated approach. We're wondering about the possibility of an "auto save" feature that will save (record to database) every 5 minutes or so the current record being edited in a section editor.

Does anyone have a proven solution for this or should I be submitting an inquiry to consulting?

Thanks for any tips.
~ Deborah