If you have a free GMail account, then you have access to Google Drive; click on the Create button, and below the standard list (document, spreadsheet, etc.) you'll see "Connect More Apps." There are at least a half-dozen flow-chart programs (that aren't limited to just flow chart objects), as well as some pretty nifty drawing and presentation programs (FloorPlanner and AutoCad 360, for example).
Warning: Some of them may actually want to charge you for use beyond 30 days; but you can always click on the Settings button to manage your apps and "disconnect" them.