The Notification integration reveals to the user a notification above the content. The Sitecore rules engine may be used to control the enabled state; simply configure the Enable rule on the script. The script is executed every time the page loads.
A Notification for the current date
Example: The following adds an information notification to the page for Sitecore 8 and a warning for Sitecore 7.
$title = "Thank you for using SPE!"
$text = "Today is $([datetime]::Now.ToLongDateString())"