A portable handheld computing device has a notification system that alerts a user of an event regardless of whether the device is on or off. The notification system has a notification mechanism that is activated upon occurrence of the event and remains active until the user acknowledges the activated mechanism. In one implementation, the notification mechanism is a light emitting diode (LED) mounted externally on the handheld computing device. The LED is visible to the user when the lid is closed onto the base (i.e., the device is off) or when the lid is open (i.e., the device is on). The notification mechanism also has a deactivation button mounted externally of the handheld computing device. The user depresses the deactivation button to deactivate the LED. The LED and deactivation button may be integrated as a single component.