Cocoa - notifications with OS X Notification Center - http://stackoverflow.com/a/11815544/291500

gistfile1.m

- (IBAction)showNotification:(id)sender{
    NSUserNotification *notification = [[NSUserNotification alloc] init];
    notification.title = @"Hello, World!";
    notification.informativeText = @"A notification";
    notification.soundName = NSUserNotificationDefaultSoundName;

    [[NSUserNotificationCenter defaultUserNotificationCenter] deliverNotification:notification];
}