Events Notifications are only notifications for your
contacts, not your own email, for example.
I can't find a script that will alert you about your own email.
What I could suggest is that you could add the Hotmail account in Plus! > Preferences > General > E-Mail Accounts. Hotmail now works with POP3, I believe. This would then alert you of new emails when busy, if you enable the option djdannyp mentioned above.