Push information to form

Is there a way to push information to another users form? A user might open a form or a report and stay on that screen for a while. If other information has changed can I show a message on the users screen.

For example if the user is looking at a report and another user adds records to the report how do I tell the first user to refresh the report to see the new information? Or if the first user is on a form and another user changes something critical to that form is there a way to display a message on the first users form?