I currently have a method that saves all the column settings from a webgrid.  These settings are then applied the next time the user comes to the page.  Currently I only save the settings when a save button is clicked and the page is posted back.  I have most of the clientside functions like sorting, column sizing and moving turned on so  the user can make a lot of changes without any postbacks.  I would like to auto save these changes with some sort of ajax call.  What is the best method to do this?  I have thought about using a timer, catching all of the different clientside events, calling a page method or hook the unBeforeUnLoad.  I would like this to be as seemless to the user as possible.

Thanks for any advise,

Eric