It would be helpful if there was a popup window that said "You are about to be signed out due to inactivity, would you like to stay logged in for (the time out setting) another 30 minutes?" Also, if you could make the browser tab or minimized browser flash to get the users attention. Then after a few minutes if the users doesn't do anything, the popup would change to say: "You have been logged out due to inactivity, please click ok to refresh your browser". It would have to work even if the tab is not active or the browser is minimized. This way people will know they are logged or timed out and will not start entering or changing data only to have it not save because they are timed out and didn't know it.